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Reaction of Co(NCS)2 with 4-methylpyridine N-oxide in methanol leads to the formation of crystals of the title compound, [Co2(NCS)4(C6H7NO)4(CH4O)2] or Co2(NCS)4(4-methylpyridine N-oxide)4(methanol)2. The asymmetric unit consist of one CoII cation, two thiocyanate anions, two 4-methylpyridine N-oxide coligands and one methanol molecule in general positions. The H atoms of one of the methyl groups are disordered and were refined using a split model. The CoII cations octahedrally coordinate two terminal N-bonded thiocyanate anions, three 4-methylpyridine N-oxide coligands and one methanol molecule. Each two CoII cations are linked by pairs of μ-1,1(O,O)-bridging 4-methylpyridine N-oxide coligands into dinuclear units that are located on centers of inversion. Powder X-ray diffraction (PXRD) investigations prove that the title compound is contaminated with a small amount of Co(NCS)2(4-methylpyridine N-oxide)3. Thermogravimetric investigations reveal that the methanol molecules are removed in the beginning, leading to a compound with the composition Co(NCS)2(4-methylpyridine N-oxide), which has been reported in the literature and which is of poor crystallinity. [ABSTRACT FROM AUTHOR]

Reaction of Co(NCS)2 with 2-methylpyridine N-oxide in a 1:3 ratio in n-butanol leads to the formation of crystals of tris(2-methylpyridine N-oxide-kO)bis-(thiocyanato-kN)cobalt(II), [Co(NCS)2(C6H7NO)3]. The asymmetric unit of the title compound consists of one CoII cation two thiocyanate anions and three crystallographically independent 2-methylpyridine N-oxide coligands in general positions. The CoII cations are trigonal-bipyramidally coordinated by two terminal N-bonding thiocyanate anions in the trans-positions and three 2-methylpyridine N-oxide coligands into discrete complexes. These complexes are linked by intermolecular C-H...S interactions into double chains that elongate in the c-axis direction. Powder X-ray diffraction (PXRD) measurements prove that all batches are always contaminated with an additional and unknown crystalline phase. Thermogravimetry and differential analysis of crystals selected by hand reveal that the title compound decomposes at about 229℃ in an exothermic reaction. At about 113℃ a small endothermic signal is observed that, according to differential scanning calorimetry (DSC) measurements, is irreversible. PXRD measurements of the residue prove that a poorly crystalline and unknown phase has formed and thermomicroscopy indicates that some phase transition occurs that is accompanied with a color change of the title compound. [ABSTRACT FROM AUTHOR]

The reaction of Co(NCS)2 with 4-methylpyridine N-oxide (C6H7NO) leads to the formation of two compounds, namely, tetrakis(4-methylpyridine N-oxide-O)bis(thiocyanato-N)cobalt(II), [Co(NCS)2(C6H7NO)4] (1), and tris(4-methylpyridine N-oxide-O)bis(thiocyanato-N)cobalt(II), [Co(NCS)2(C6H7NO)3] (2). The asymmetric unit of 1 consists of one CoII cation located on a centre of inversion, as well as one thiocyanate anion and two 4-methylpyridine N-oxide coligands in general positions. The CoII cations are octahedrally coordinated by two terminal N-bonding thiocyanate anions in trans positions and four 4-methylpyridine N-oxide ligands. In the extended structure, these complexes are linked by C--H...O and C--H...S interactions. In compound 2, two crystallographically independent complexes are present, which occupy general positions. In each of these complexes, the CoII cations are coordinated in a trigonal-bipyramidal manner by two terminal N-bonding thiocyanate anions in axial positions and by three 4-methylpyridine N-oxide ligands in equatorial positions. In the crystal, these complex molecules are linked by C--H...S interactions. For compound 2, a nonmerohedral twin refinement was performed. Powder X-ray diffraction (PXRD) reveals that 2 was nearly obtained as a pure phase, which is not possible for compound 1. Differential thermoanalysis and thermogravimetry data (DTA-TG) show that compound 2 start to decompose at about 518K. [ABSTRACT FROM AUTHOR]

Reaction of CoBr2 with 2-methylpyridine N-oxide in n-butanol leads to the formation of the title compound, [CoBr2(C6H7NO)2] or [CoBr2(2-methylpyridine N-oxide)2]. Its asymmetric unit consists of one CoII cation as well as two bromide anions and two 2-methylpyridine N-oxide coligands in general positions. The CoII cations are tetrahedrally coordinated by two bromide anions and two 2-methylpyridine N-oxides, forming discrete complexes. In the crystal structure, these complexes are linked predominantly by weak C-H...Br hydrogen bonding into chains that propagate along the crystallographic a-axis. Powder X-ray diffraction (PXRD) measurements indicate that a pure phase was obtained. Thermoanalytical investigations prove that the title compound melts before decomposition; before melting, a further endothermic signal of unknown origin was observed that does not correspond to a phase transition. [ABSTRACT FROM AUTHOR]

The title compound, [Co(NCS)2(C6H7NO)]n or Co(NCS)2(2-methylpyridine Noxide), was prepared by the reaction of Co(NCS)2 and 2-methylpyridine Noxide in methanol. All crystals obtained by this procedure show reticular pseudo-merohedric twinning, but after recrystallization, one crystal was found that had a minor component with only a very few overlapping reflections. The asymmetric unit consists of one CoII cation, two thiocyanate anions and one 2-methylpyridine N-oxide coligand in general positions. The CoII cations are octahedrally coordinated by two O-bonding 2-methylpyridine N-oxide ligands, as well as two S- and two N-bonding thiocyanate anions, and are connected via μ-1,3(N,S)-bridging thiocyanate anions into chains that are linked by μ-1,1(O, O) bridging coligands into layers. No pronounced directional intermolecular interactions are observed between the layers. The 2-methylpyridine coligand is disordered over two orientations and was refined using a split model with restraints. Powder X-ray diffraction (PXRD) indicates that a pure sample was obtained and IR spectroscopy confirms that bridging thiocyanate anions are present. Thermogravimetry and differential thermoanalysis (TG-DTA) shows one poorly resolved mass loss in the TG curve that is accompanied by an exothermic and an endothermic signal in the DTA curve, which indicate the decomposition of the 2-methylpyridine N-oxide coligands. [ABSTRACT FROM AUTHOR]

Reaction of FeCl2·4H2O with KSCN and 3-cyano­pyridine (pyridine-3-carbo­nitrile) in ethanol accidentally leads to the formation of single crystals of Fe(NCS)(Cl)(3-cyano­pyridine)4 or [FeCl(NCS)(C6H4N2)4]. The asymmetric unit of this compound consists of one FeII cation, one chloride and one thio­cyanate anion that are located on a fourfold rotation axis as well as of one 3-cyano­pyridine coligand in a general position. The FeII cations are sixfold coordinated by one chloride anion and one terminally N-bonding thio­cyanate anion in trans-positions and four 3-cyano­pyridine coligands that coordinate via the pyridine N atom to the FeII cations. The complexes are arranged in columns with the chloride anions, with the thio­cyanate anions always oriented in the same direction, which shows the non-centrosymmetry of this structure. No pronounced inter­molecular inter­actions are observed between the complexes. Initially, FeCl2 and KSCN were reacted in a 1:2 ratio, which lead to a sample that contains the title compound as the major phase together with a small amount of an unknown crystalline phase, as proven by powder X-ray diffraction (PXRD). If FeCl2 and KSCN is reacted in a 1:1 ratio, the title compound is obtained as a nearly pure phase. IR investigations reveal that the CN stretching vibration for the thio­cyanate anion is observed at 2074 cm−1, and that of the cyano group at 2238 cm−1, which also proves that the anionic ligands are only terminally bonded and that the cyano group is not involved in the metal coordination. Measurements with thermogravimetry and differential thermoanalysis reveal that the title compound decomposes at 169°C when heated at a rate of 4°C min−1 and that the 3-cyano­pyridine ligands are emitted in two separate poorly resolved steps. After the first step, an inter­mediate compound with the composition Fe(NCS)(Cl)(3-cyano­pyridine)2 of unknown structure is formed, for which the CN stretching vibration of the thio­cyanate anion is observed at 2025 cm−1, whereas the CN stretching vibration of the cyano group remain constant. This strongly indicates that the FeII cations are linked by μ-1,3-bridg­ing thio­cyanate anions into chains or layers. [ABSTRACT FROM AUTHOR]

Reaction of CoBr2 with 2-methylpyridine N-oxide in n-butanol leads to the formation of the title compound, [CoBr2]2(2-methylpyridine N-oxide)4⋅-n-butanol or [Co2Br4(C6H7NO)4]⋅C4H10O. The asymmetric unit of the title compound consists of one CoII cation as well as two bromide anions and two 2-methylpyridine N-oxide coligands in general positions and one n-butanol molecule that is disordered around a center of inversion. The CoII cations are fivefold coordinated by two bromide anions and one terminal as well as two bridging 2-methylpyridine N-oxide and linked by two symmetry-related μ-1,1(O,O) 2-methylpyridine N-oxide coligands into dinuclear units that are located on centers of inversion. In the crystal structure, the dinuclear units are also connected via pairs of C--H⋯Br hydrogen bonds into chains that elongate in the b-axis direction. The n-butanol molecules are located between the chains and are linked via O--H⋯Br hydrogen bonds each to one chain. Powder X-ray diffraction (PXRD) measurements reveal that a pure phase has been obtained. Measurements using thermogravimetry and differential thermoanalysis shows one mass loss up to 523 K, in which the n-butanol molecules are removed. PXRD measurements of the residue obtained after n-butanol removal shows that a completely different crystalline phase has been obtained and IR investigations indicate significant structural changes in the Co coordination. [ABSTRACT FROM AUTHOR]

The reaction of cobalt dichloride hexahydrate with pyridazine leads to the formation of crystals of the title compound, [CoCl2(C4H4N2)]n. This compound is isotypic to a number of compounds with other divalent metal ions. Its asymmetric unit consists of a Co2+ atom (site symmetry 2/m), a chloride ion (site symmetry m) and a pyridazine molecule (all atoms with site symmetry m). The Co2+ cations are coordinated by four chloride anions and two pyridazine ligands, generating trans-CoN4Cl2 octahedra, and are linked into [010] chains by pairs of μ-1,1-bridging chloride anions and bridging pyridazine ligands. In the crystal structure, the pyridazine ligands of neighboring chains are stacked onto each other, indicating π-π interactions. Powder X-ray diffraction proves that a pure crystalline phase was obtained. Differential thermonalysis coupled to thermogravimetry (DTA--TG) reveal that decomposition is observed at about 710 K. Magnetic measurements indicate low-temperature metamagnetic behavior as already observed in a related compound. [ABSTRACT FROM AUTHOR]

The title compound, [Co(SCN)2(C6H4N2O)4], was prepared by the reaction of cobalt(II)thiocyanate with 3-cyanopyridine N-oxide in ethanol. In the crystal, the cobalt(II) cations are octahedrally coordinated by two terminal N-bonded thiocyanate anions and four O-bonded 3-cyanopyridine N-oxide coligands, forming discrete complexes that are located on centers of inversion, hence forming trans-CoN2O4 octahedra. The structure refinement was performed in the monoclinic space group P21/n, for which a potential lattice translation and new symmetry elements with a fit of 100% is suggested. The structure can easily be refined in the space group I2/m, where the complexes have 2/m symmetry. However, nearly all of the reflections that violate the centering are observed with significant intensity and the refinement in P21/n leads to significantly lower R(F) values (0.027 versus 0.033). Moreover, in I2/m much larger components of the anisotropic displacement parameters are observed and therefore, the crystal structure is presented in the primitive unit cell. IR investigations confirm that the anionic ligands are only terminally bonded and that the cyano group is not involved in the metal coordination. PXRD investigations show that a pure crystalline phase has been obtained and measurements using simultaneously thermogravimetry and differential thermoanalysis reveal that the compound decomposes in an exothermic reaction upon heating, without the formation of a coligand-deficient intermediate phase. [ABSTRACT FROM AUTHOR]

Four compounds with the composition Cd(NCSe)2(3‐ClPy)4 (1), [Cd(NCSe)2(3‐ClPy)2] ⋅ 3‐ClPy (2), Cd(NCSe)2(3‐ClPy)2 (3) and Cd(NCSe)2(3‐ClPy) (4) with 3‐ClPy = 3‐chloropyridine were synthesized. In the structure of 1 discrete complexes are observed, whereas in 2 the Cd cations are linked by pairs of selenocyanato anions into chains and between the chains 3‐chloropyridine solvate molecules are embedded. In compound 3 each two Cd cations are linked by pairs of anionic ligands into dinuclear units, that are further connected into layers by μ‐1,3 single bridging selenocyanate anions. In compound 4, both, octahedrally and tetrahe‐ drally coordinated Cd cations are present, that are linked by μ‐1,3‐ bridging anionic ligands into a three‐.dimensional network. Thermoanalytical investigations prove that compound 1 loses the 3‐chloropyridine ligands stepwise upon heating and transforms into compound 4via compound 3 as an intermediate. Further investigations show that the thiocyanate analogue Cd(NCS)2(3‐ClPy) 5 that is not reported in the literature can also be prepared. Since no single crystals were available, the structure was solved from PXRD data and refined using the Rietveld method, which revealed that this compound is an isomer of 4. In its crystal structure the Cd cations are linked by μ‐1,3(N,S) and μ‐1,3,3(N,S,S)‐bridging anionic ligands into chains that are further connected via Cd2S2 rings into double chains. [ABSTRACT FROM AUTHOR]

Reaction of zinc(II) chloride, bromide and iodide with 2-methylpyrazine (2-Mepyz) leads to the formation of coordination compounds with the composition ZnX2(2-Mepyz)2 (X = Cl; 1-Cl, Br; 1-Br and I; 1-I). In the compounds each Zn cation is tetrahedrally coordinated by two halide anions and two 2-methylpyrazine ligands forming discrete complexes. TG-DTA and temperature dependent PXRD measurements prove that upon heating compounds 1 transform into new compounds with the composition ZnX2(2-Mepyz) (2), that are subsequently converted into compounds with the composition (ZnX2)3(2-Mepyz) (3) upon further heating. It was also found that compounds 2 can be prepared directly in solution. For ZnI2(2-Mepyz) (2-I) crystals were obtained and characterized by single crystal X-ray diffraction, whereas the crystal structures of 2-Cl and 2-Br were determined ab initio from PXRD data. In these compounds the Zn cations are also tetrahedrally coordinated and linked into chains by bridging 2-methylpyrazine ligands. The (ZnX2)3(2-Mepyz) compounds can only be obtained by thermal decomposition, and the products are of poor crystallinity and extremely hygroscopic, which prevented structure determinations. [ABSTRACT FROM AUTHOR]

The reactions of cadmium bromide and cadmium iodide with pyridazine (C4H4N2) in ethanol under solvothermal conditions led to the formation of crystals of [CdBr2(pyridazine)]n (1) and [CdI2(pyridazine)]n (2), which were characterized by single-crystal X-ray diffraction. The asymmetric units of both compounds consist of a cadmium cation located on the intersection point of a twofold screw axis and a mirror plane (2/m), a halide anion that is located on a mirror plane and a pyridazine ligand, with all atoms occupying Wyckoff position 4e (mm2). These compounds are isotypic and consist of cadmium cations that are octahedrally coordinated by four halide anions and two pyridazine ligands and are linked into [100] chains by pairs of μ-1,1-bridging halide anions and bridging pyridazine ligands. In the crystals, the pyridazine ligands of neighboring chains are stacked onto each other, indicating π-π interactions. Larger amounts of pure samples can also be obtained by stirring at room-temperature, as proven by powder X-ray diffraction. Measurements using thermogravimetry and differential thermoanalysis (TG-DTA) reveal that upon heating all the pyridiazine ligands are removed in one step, which leads to the formation of CdBr2 or CdI2. [ABSTRACT FROM AUTHOR]

Reaction of copper(I) iodide in pure 2-chloro-pyrazine leads to the formation of a few crystals of the title compound, [Cu2I2(C4H3ClN2)4] or (CuI)2(2-chloro-pyrazine)4, which was characterized by single-crystal X-ray diffraction. In its crystal structure, the CuI cations are each tetra-hedrally coordinated by two iodide anions and two 2-chloro-pyrazine ligands and are linked into binuclear complexes consisting of (CuI)2 rings located on centers of inversion. PXRD investigations of a few crystals obtained from the suspension indicate that the title compound is contaminated with a small amount of the 2-chloro-pyrazine-deficient compound CuI(2-chloro-pyrazine) already reported in the literature. PXRD investigations prove that the title compound immediately decomposes at room temperature into CuI(2-chloro-pyrazine) and this might be the reason why no pure samples can be obtained. TDA-TG-MS investigations shows two mass losses, the first of which corresponds to the formation of CuI(2-chloro-pyrazine), whereas in the second mass loss CuI is formed. [ABSTRACT FROM AUTHOR]

The reactions of Zn(NO3)2.6H2O and Cd(NO3)2.4H2O with KSeCN and 4-meth­yl­pyridine (C6H7N; 4-picoline) lead to the formation of crystals of bis­(4-methyl­pyridine-κN)bis­(seleno­cyanato-κN)zinc(II), [Cd(NCSe)2(C6H7N)2] (1), and catena-poly[[bis­(4-methyl­pyridine-κN)cadmium(II)]-di-μ-seleno­cyanato-κ2N:Se;κ2Se:N], [Cd(NCSe)2(C6H7N)2]n (2), suitable for single-crystal X-ray diffraction. The asymmetric unit of compound 1 consists of one Zn cation that is located on a twofold rotation axis as well as one seleno­cyanate anion and one 4-methyl­pyridine ligand in general positions. The Zn cations are tetra­hedrally coordinated by two terminal N-bonding thio­cyanate anions and two 4-methyl­pyridine ligands, forming discrete complexes. The asymmetric unit of compound 2 consists of two crystallographically independent Cd cations, of which one is located on a twofold rotation axis and the second on a center of inversion, as well as two crystallographically independent seleno­cyanate anions and two crystallographically independent 4-methyl­pyridine ligands in general positions. The Cd cations are octa­hedrally coordinated by two N- and two S-bonding seleno­cyanate anions and two 4-methyl­pyridine ligands and are linked into chains by pairs of seleno­cyanate anions. Within the chains, the Cd cations show an alternating cis-cis-trans and all-trans coordination and therefore, the chains are corrugated. PXRD investigations prove that the Zn compound was obtained as a pure phase and that the Cd compound contains a very small amount of an additional and unknown phase. In the IR spectrum of 1, the CN stretching vibration of the seleno­cyanate anion is observed at 2072 cm-1, whereas in the 2 it is shifted to 2094 cm-1, in agreement with the crystal structures. [ABSTRACT FROM AUTHOR]

Reaction of Ni(NCS)2 with 3-methylpyridine in water leads to the formation of crystals of the title compound, [Ni(NCS)2(C6H7N)4]. All of them are of poor quality and non-merohedrally twinned but a refinement using data in HKLF-5 format leads to a reasonable structure model and reliability factors. The crystal structure of the title compound consists of discrete complexes, in which the nickel cations are sixfold coordinated by two terminal N-bonded thiocyanate anions and four 3-methylpyridine ligands within slightly distorted octahedra. One of the 3-methylpyridine ligands is disordered and was refined using a split model. The discrete complexes are arranged into layers. X-ray powder diffraction proves that pure samples have been obtained, and in the IR spectrum, the CN stretching vibration is observed at 2072 cm-1, in agreement with the presence of only terminally coordinated thiocyanate anions. Comparing the calculated powder pattern with those of the residues obtained by solvent removal from several solvates already reported in the literature proves that, in each case, this crystalline phase is formed. Assessing the crystal structures of the solvates in comparison with that of the ansolvate reveals some similarities. [ABSTRACT FROM AUTHOR]

Single crystals of the title compound, [Co(NCS)2(C5H4BrN)2(C2H3N)2], were obtained by the reaction of Co(NCS)2 with 3-bromopyridine in acetonitrile. The CoII cations lie on crystallographic inversion centers and are coordinated by two N-bonded thiocyanate anions, two 3-bromopyridine and two acetonitrile ligands thereby forming slightly distorted CoN6 octahedra. In the crystal, these complexes are linked by C--H...S and C--H...N hydrogen bonds into a threedimensional network. In the direction of the crystallographic b-axis, the complexes are arranged into columns with neighboring 3-bromopyridine ligands stacked onto each other, indicating π-π interactions. The CN stretching vibration of the thiocyanate anions is observed at 2066 cm-1, in agreement with the presence of only N-bonded anionic ligands. TG-DTA measurements reveal that in the first mass loss the acetonitrile ligands are removed and that in the second step, half of a 3-bromopyridine ligand is lost, leading to the formation of a polymeric compound with the composition [(Co(NCS)2)2(C5H4BrN)3]n already reported in the literature. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, {[Ni(NCS)2(C6H7N)2]·CH3CN}n, the NiII cation is octahedrally coordinated by two N-bonding and two S-bonding thiocyanate anions, as well as two 3-methylpyridine coligands, with the thiocyanate S atoms and the 3-methylpyridine N atoms in cis-positions. The metal cations are linked by pairs of thiocyanate anions into chains that, because of the cis-cis-trans coordination, are corrugated. These chains are arranged in such a way that channels are formed in which disordered acetonitrile solvate molecules are located. This overall structural motif is very similar to that observed in Ni(NCS)2[4-(boc-amino)pyridine]2·CH3CN reported in the literature. At room temperature, the title compound loses its solvent molecules within a few hours, leading to a crystalline phase that is structurally related to that of the pristine material. If the ansolvate is stored in an acetonitrile atmosphere, the solvate is formed again. Single-crystal X-ray analysis at room-temperature proves that the crystals decompose immediately, presumably because of the loss of solvent molecules, and from the reciprocal space plots it is obvious that this reaction, in contrast to that in Ni(NCS)2[4-(boc-amino)pyridine]2·CH3CN, does not proceed via a topotactic reaction. [ABSTRACT FROM AUTHOR]

The reaction of nickel(II)thiocyanate with 3-methylpyridine (3-picoline; C6H7N) in different solvents leads to the formation of crystals of bis(isothiocyanato-κN)tetrakis(3-methylpyridine-κN)nickel(II) as the ethanol disolvate, [Ni(NCS)2- (C6H7N)4]-2C2H5OH (1), the acetonitrile disolvate, [Ni(NCS)2(C6H7N)4]•- 2CH3CN (2), and the diethyl ether monosolvate, [Ni(NCS)2(C6H7N)4]-C4H10O (3). The crystal structures of these compounds consist of NiII cations coordinated by two N-bonded thiocyanate anions and four 3-methylpyridine ligands to generate NiN6 octahedra with the thiocyanate groups in a trans orientation. In compounds 1 and 2 these complexes are located on centers of inversion, whereas in compound 3, they occupy general positions. In the crystal structures, the complexes are packed in such a way that cavities are formed in which the solvent molecules are located. Compounds 1 and 2 are isotypic, which is not the case for compound 3. In compounds 1 and 2 the solvate molecules are disordered, whereas they are fully ordered in compound 3. Disorder is also observed for one of the 3-methylpyridine ligands in compound 2. Powder X-ray diffraction and IR measurements show that at room temperature all compounds decompose almost immediately into the same phase, as a result of the loss of the solvent molecules. [ABSTRACT FROM AUTHOR]

Reactions of Mn(NCS)2 with 3-bromopyridine in acetonitrile lead to the formation of Mn(NCS)2(3-bromopyridine)4 (1) and Mn(NCS)2(3-bromopyridine)2(MeCN)2 (2) that were characterized by single crystal X-ray diffraction. Compounds 1 and 2 consist of discrete complexes, in which the Mn(II) cations are octahedrally coordinated by two trans-N-bonding thiocyanate anions and four pyridine (1) or two pyridine and two acetonitrile ligands (2). Thermoanalytical measurements on 1 and 2 have shown that upon heating half of the 3-bromopyridine co-ligands from 1 or both acetonitrile ligands from 2 are removed leading to a crystalline phase with the composition [Mn(NCS)2(3-bromopyridine)2]n (3-II). From dry n-butanol a phase with the same composition was obtained (3-I) that corresponds to a polymorphic or isomeric form of 3-II. Crystal structure analysis of 3-I shows that in this form the Mn cations are linked by pairs of anionic ligands into linear chains. The results of magnetic measurements on 3-I show antiferromagnetic interactions along the chains and the analysis of the magnetic susceptibility using the Fisher model for chains gave a J value of −5.76(5) K. [ABSTRACT FROM AUTHOR]

The reaction of Mn(NCS)2 with 3‐cyanopyridine in water accidentally leads to the formation of single crystals of Mn(NCS)2(H2O)2 (1). If the synthesis is performed without 3‐cyanopyridine, the known tetrahydrate Mn(NCS)2(H2O)4 is formed. In the crystal structure of the new hydrate, the Mn2+ cations are linked by pairs of μ‐1,3‐bridging anionic ligands to chains, which are further connected via Mn(NCS)2(H2O)4 units into layers, that are additionally stabilized by intralayer hydrogen bonding. These layers are linked by interlayer hydrogen bonding into a 3D network. The structure of 1 shows strong similarities to that of both the tetrahydrate and of Mn(NCS)2. The synthesis from water always leads to the tetrahydrate, which is also obtained, when Mn(NCS)2 is stored in a humid atmosphere. Thermoanalytical measurements on the tetrahydrate show a more complicated behavior, which includes melting at about 46 °C and on cooling sometimes the dihydrate is observed. If the tetrahydrate is stored in vacuum at room temperature, the dihydrate forms before the transformation to the anhydrate is observed. Isothermic water sorption measurements prove, that at low humidity the dihydrate is obtained, which transforms into the tetrahydrate at higher humidities. [ABSTRACT FROM AUTHOR]

The reaction of Co(NCS)2 with urotropine in ethanol leads to the formation of two different compounds, namely, bis(ethanol-κO)bis(hexamethylenetetramine-κN)bis(thiocyanato-κN)cobalt(II)-diaqua-κ²O-bis(hexamethylenetetramine-κN)bis(thiocyanato-κN)cobalt(II)-ethanol-hexamethylenetetramine (1.2/0.8/1.6/4), [Co(NCS)2(C6H12N4)2(C2H6O)2]1.2·[Co(NCS)2(C6H12N4)2(H2O)2]0.8·1.6C2H6O·4C6H12N4, 1, and tris(ethanol-κO)(hexamethylenetetramine-κN)bis(thiocyanato-κN)cobalt(II), [Co(NCS)2(C6H12N4)(C2H6O)3], 2. In the crystal structure of compound 1, two crystallographically independent discrete complexes are observed that are located on centres of inversion. In one of them, the Co cation is octahedrally coordinated to two terminal N-bonded thiocyanate anions, two urotropine ligands and two ethanol molecules, whereas in the second complex 80% of the coordinating ethanol is exchanged by water. Formally, compound 1 is a mixture of two different complexes, i.e. diaquadithiocyanatobis(urotropine)cobalt(II) and diethanoldithiocyanatobis(urotropine)cobalt(II), that contain additional ethanol and urotropine solvate molecules leading to an overall composition of [Co(NCS)2(urotropine)2(ethanol)1.2(H2O)0.8·0.8ethanol·4urotropine. Both discrete complexes are linked by intermolecular O--H···O and O--H···N hydrogen bonding and additional urotropine solvate molecules into chains, which are further connected into layers. These layers combine into a three-dimensional network by pairs of centrosymmetric intermolecular C--H···S hydrogen bonds. In the crystal structure of compound 2, dithiocyanato(urotropine)triethanolcobalt(II), the cobalt cation is octahedrally coordinated to two terminal N-bonded thiocyanate anions, one urotropine ligand and three ethanol molecules into discrete complexes, which are located in general positions. These complexes are linked by intermolecular O--H···N hydrogen bonding into layers, which are further connected into a three-dimensional network by intermolecular C--H···S hydrogen bonding. [ABSTRACT FROM AUTHOR]

Crystals of the title compound, [Co(NCS)2(C13H24N2S)2], were obtained by the reaction of Co(NCS)2 with 1,3-dicyclohexylthiourea in ethanol. Its crystal structure consists of discrete complexes that are located on twofold rotation axes, in which the CoII cations are tetrahedrally coordinated by two terminal Nbonded thiocyanate anions and two 1,3-dicyclohexylthiourea ligands. These complexes are linked via intermolecular N--H...S and C--H...S hydrogen bonding into chains, which elongate in the b-axis direction. These chains are closely packed in a pseudo-hexagonal manner. The CN stretching vibration of the thiocyanate anions located at 2038 cm-1 is in agreement with only terminal bonded anionic ligands linked to metal cations in a tetrahedral coordination. TG-DTA measurements prove the decomposition of the compound at about 227+C. DSC measurements reveal a small endothermic signal before decomposition at about 174+C, which might correspond to melting. [ABSTRACT FROM AUTHOR]

The reaction of one equivalent Co(NCS)2 with four equivalents of urotropine (hexamethylenetetramine) in ethanol leads to the formation of two compounds, namely, bis(ethanol-°O)bis(thiocyanato-°N)bis(urotropine-°N)cobalt(II), [Co(NCS)2(C6H12N4)2(C2H6O)2] (1), and tetrakis(ethanol-°O)bis(thiocyanato-°N)cobalt(II)-urotropine (1/2), [Co(NCS)2(C2H6O)4]°2C6H12N4 (2). In 1, the Co cations are located on centers of inversion and are sixfold coordinated by two terminal N-bonded thiocyanate anions, two ethanol and two urotropine ligands whereas in 2 the cobalt cations occupy position Wyckoff position c and are sixfold coordinated by two anionic ligands and four ethanol ligands. Compound 2 contains two additional urotropine solvate molecules per formula unit, which are hydrogen bonded to the complexes. In both compounds, the building blocks are connected via intermolecular O--H...N (1 and 2) and C--H...S (1) hydrogen bonding to form three-dimensional networks. [ABSTRACT FROM AUTHOR]

Single crystals of the high-temperature form I of [Co(NCS)2(DMAP)2] (DMAP = 4-dimethylaminopyridine, C7H10N2) were obtained accidentally by the reaction of Co(NCS)2 with DMAP at slightly elevated temperatures under kinetic control. This modification crystallizes in the monoclinic space group P21/m and is isotypic with the corresponding Zn compound. The asymmetric unit consists of one crystallographically independent Co cation and two crystallographically independent thiocyanate anions that are located on a crystallographic mirror plane and one DMAP ligand (general position). In its crystal structure the discrete complexes are linked by C--H...S hydrogen bonds into a three-dimensional network. For comparison, the crystal structure of the known low-temperature form II, which is already thermodynamically stable at room temperature, was redetermined at the same temperature. In this polymorph the complexes are connected by C--H...S and C--H...N hydrogen bonds into a three-dimensional network. At 100 K the density of the high-temperature form I (· = 1.462 g cmC3) is higher than that of the low-temperature form II (B = 1.457 g cmC3), which is in contrast to the values determined by XRPD at room temperature. Therefore, these two forms represent an exception to the Kitaigorodskii density rule, for which extensive intermolecular hydrogen bonding in form II might be responsible. [ABSTRACT FROM AUTHOR]

The reaction of Mn(NCS)2 with a stoichiometric amount of 3-(aminomethyl) pyridine in ethanol led to the formation of the title compound, [Mn(NCS)2(C6H8N2)2]n, which is isotypic to its Zn, Co and Cd analogues. The manganese cation is located on a centre of inversion and is octahedrally coordinated in an all-trans configuration by two terminal N-bonded thiocyanate anions as well as four 3-(aminomethyl)pyridine co-ligands, of which two coordinate with the pyridine N atom and two with the amino N atom. The 3-(aminomethyl)pyridine co-ligands connect the MnII cations into layers extending parallel to (101). These layers are further connected into a threedimensional network by relatively strong intermolecular N-H=S hydrogen bonding. Comparison of the experimental X-ray powder diffraction pattern with the calculated pattern on the basis of single-crystal data proves the formation of a pure crystalline phase. IR measurements showed the CN stretching vibration of the thiocyanate anions at 2067 cm-1, which is in agreement with the presence of terminally N-bonded anionic ligands. TG-DTA measurements revealed that the title compound decomposes at about 500 K. [ABSTRACT FROM AUTHOR]

The reaction of Co(NCS)2 with 3-(aminomethyl)pyridine as coligand leads to the formation of crystals of the title compound, [Co(NCS)2(C6H8N2)2]n, that were characterized by single-crystal X-ray analysis. In the crystal structure, the CoII cations are octahedrally coordinated by two terminal N-bonded thiocyanate anions as well as two pyridine and two amino N atoms of four symmetry-equivalent 3-(aminomethyl)pyridine coligands with all pairs of equivalent atoms in a trans position. The CoII cations are linked by the 3-(aminometh-yl)pyridine coligands into layers parallel to the ac plane. These layers are further linked by intermolecular N--H⋯S hydrogen bonding into a three-dimensional network. The purity of the title compound was determined by X-ray powder diffraction and its thermal behavior was investigated by differential scanning calorimetry and thermogravimetry. [ABSTRACT FROM AUTHOR]

Reaction of MX2 (M = Cd, Zn; X = Cl, Br, I) with 2‐cyanopyrazine leads to the formation of compounds with the composition CdX2(2‐cyanopyrazine)2 (X = Cl; CdCl, X = Br; CdBr and X = I; CdI) and ZnX2(2‐cyanopyrazine)2 (X = Cl; ZnCl, X = Br; ZnBr and X = I; ZnI/I). In the crystal structures of the Cd compounds and in ZnCl, the metal cations are octahedrally coordinated and are linked into chains by the halide anions via common edges. In contrast, in the crystal structures of ZnBr and ZnI/I the metal cations are tetrahedrally coordinated into discrete complexes. Further investigations show that a second modification of ZnCl2(2‐cyanopyrazine)2 exists (ZnI/II), which is formed by kinetic control. The thermal properties of the 2‐cyanopyrazine rich compounds were investigated by TG‐DTA and temperature dependent XRPD measurements. Upon heating the Cd compounds, all 2‐cyanopyrazine ligands are removed in a single step with no indication of the formation of a 2‐cyanopyrazine deficient phase. A similar behavior is observed for ZnI, whereas for ZnCl and ZnBr, TG‐DTA measurements suggest the formation of a 2‐cyanopyrazine deficient phase that, in case of ZnBr, cannot be isolated and, for ZnCl, cannot be obtained pure. The emission of these compounds is shifted from the blue to orange depending on the crystal structure and the nature of the halide anion. [ABSTRACT FROM AUTHOR]

The room temperature reaction of Na4Sn2S6·5H2O with CoCl2·6H2O and 2‐(aminomethyl)pyridine (2‐AMP) or trans‐1,2‐diamino‐cyclohexane (DACH) leads to crystallization of two compounds with the compositions [Co(2‐(aminomethyl)pyridine)3]2 Sn2S6·10H2O (1) and [Co(trans‐1,2‐diaminocyclohexane)3]2Sn2S6·8H2O (2). In both compounds [Sn2S6]4– anions are present that are charge balanced each by two Co2+ centered complexes. Each of the two CoII cations are sixfold coordinated by six N atoms of three 2‐AMP or DACH ligands within slightly distorted octahedra. In compound 1, the two complexes are linked by one [Sn2S6]4– anion via strong N–H···S hydrogen bonds into centrosymmetric charge neutral trimeric units, that are further linked by weak C–H···S and N–H···S hydrogen bonds into chains that are directed along the a axis. These chains are further joined by N–H···O and O–H···O hydrogen bonds into a 3D network, with the H2O molecules forming chains along the b axis. The crystal structure of 2 is similar to that of 1 featuring trimeric units which are also linked into chains. Between the chains water molecules are embedded that link the chains into a 3D network. Upon heating 2 in a thermobalance the water and ligand molecules are removed in discrete steps, indicating that compounds with more condensed thiostannate networks will form. [ABSTRACT FROM AUTHOR]

Five new compounds with the compositions [Cd(NCS)2(3-cyanopyridine)2]n · 3-cyanopyridine (1), [Cd(NCS)2(3-cyanopyridine)2]n · 1/3 3-cyanopyridine (2), [Cd(NCS)2(3-cyanopyridine)2]n (3), {[Cd(NCS)2]2(3-cyanopyridine)3}n (4), and {[Cd(NCS)2]3(3-cyanopyridine)4}n (5) have been obtained by the reaction of Cd(NCS)2 with 3-cyanopyridine in different solvents. While large amounts of compounds 1–4 could be prepared as powders, only a few single crystals of 5 were accidently obtained. Thermoanalytical investigations have shown that 4 could also be obtained by annealing of 1 or 2 and that under slightly different conditions 5 could be obtained as part of a mixture with 4. The crystal structures of all compounds can be divided in two sets of compounds. Compounds 1, 2 and 3 consist of chains in which the Cd cations show three different coordination environments and in which the coligands are only terminally bonded. In the structures of 4 and 5 similar chains are observed, which are connected into layers via some of the 3-cyanopyridine coligands. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, (C5H6N)[Cr(NCS)4(C5H5N)2]·C5H5N, the CrIII ions are octa­hedrally coordinated by four N-bonding thio­cyanate anions and two pyridine ligands into discrete negatively charged complexes, with the CrIII ion, as well as the two pyridine ligands, located on crystallographic mirror planes. The mean planes of the two pyridine ligands are rotated with respect to each other by 90°. Charge balance is achieved by one protonated pyridine mol­ecule that is hydrogen bonded to one additional pyridine solvent mol­ecule, with both located on crystallographic mirror planes and again rotated by exactly 90°. The pyridinium H atom was refined as disordered between both pyridine N atoms in a 70:30 ratio, leading to a linear N—H· · ·N hydrogen bond. In the crystal, discrete complexes are linked by weak C—H· · ·S hydrogen bonds into chains that are connected by additional C—H· · ·S hydrogen bonding via the pyridinium cations and solvent mol­ecules into layers and finally into a three-dimensional network. [ABSTRACT FROM AUTHOR]

The reaction of different stoichiometric amounts of Zn(NCS)2 with 3‐cyanopyridine in different solvents leads to the formation of several new coordination compounds, which were structurally characterized and investigated for their thermal behavior. In Zn(NCS)2(3‐cyanopyridine)4 (1) and Zn(NCS)2(3‐cyanopyridine)2(H2O)2·(3‐cyanopyridine)2 (2) the zinc cations are octahedrally coordinated by two terminally N‐bonded thiocyanate anions and four 3‐cyanopyridine (1) or two 3‐cyanopyridine and two water molecules (2) within slightly distorted octahedra. Zn(NCS)2(3‐cyanopyridine)2 (3) and Zn(NCS)2(3‐cyanopyridine)2·(H2O)0.5 (3‐H2O) also form discrete complexes but with tetrahedrally coordinated Zn cations. Upon heating compound 1 decomposes without the formation of any intermediate compound. In contrast, compound 2 loses the water molecules in the first step and transforms into compound 1. Surprisingly, upon further heating a second TG step is observed, in which compound 3 is formed as an intermediate, which is not observed if compound 1 is heated directly. The tetrahedral complex 3 melts leading to the formation of an amorphous phase. If the hemihydrate 3‐H2O is heated, it transforms into 3 via melting and crystallization but there are hints that a metastable phase might form as intermediate on water removal. [ABSTRACT FROM AUTHOR]

Reaction of Co(NCS)2 with 4‐dimethylaminopyridine (DMAP) leads to the formation of four new compounds. The crystal structures of Co(NCS)2(DMAP)2(H2O)2·2H2O (1), Co(NCS)2(DMAP)2(MeOH)2 (2) and Co(NCS)2(DMAP)2(MeCN)2 (3) consist of discrete simple solvato complexes in which the Co cations are octahedrally coordinated by two terminally N‐bonded thiocyanate anions, two DMAP ligands as well as two solvato ligands. Co(NCS)2(DMAP)2 (4/II) also forms discrete complexes, but the Co cations are tetrahedral coordinated by two anionic ligands and two DMAP ligands. Upon heating, the hydrate 1 transforms into 4/II, whereas the methanol solvate 2 transforms into a new polymorphic modification of Co(NCS)2(DMAP)2 (4/I). For structure determination the corresponding Zn(NCS)2 compound was prepared that is isotypic to 4/I. Solvent mediated conversion experiments prove that 4/II represents the thermodynamic stable form at room‐temperature and density functional theory (DFT) calculations indicate that this form is also stable at 0 K. Upon heating both modifications show melting with the higher melting polymorph 4/I having the lower melting enthalpy. Temperature dependent X‐ray powder diffraction shows that 4/II transforms into 4/I upon heating. All experimental results indicate, that both modifications are related by enantiotropism. Two polymorphic Co(NCS)2 coordination compounds were synthesized by solvent removal from different precursors, structurally characterized and investigated for their stability, thermodynamic relations and transition behaviour. Both forms are related by enantiotropism and the thermodynamic transition temperature was estimated from their melting enthalpies and confirmed by annealing experiments. [ABSTRACT FROM AUTHOR]

Reaction of Co(NCS)2 or Ni(NCS)2 with pyridine-4-thioamide in different solvents led to the formation of two compounds with composition [Co(NCS)2(C2H3N)(C6H6N2S)3]·2CH3CN (1) and [Ni(NCS)2(C6H6N2S)4]·-5CH3OH (2), respectively. The asymmetric unit of compound 1 consists of one cobalt(II) cation, two thiocyanate anions, three pyridine-4-thioamide ligands, one coordinating and two solvate acetonitrile molecules. One of the two acetonitrile solvate molecules is disordered over two sets of sites in a 0.62:0.38 ratio. The asymmetric unit of compound 2 comprises of one nickel(II) cation, two thiocyanate anions, four N-bonding pyridine-4-thioamide ligands and five methanol solvate molecules. In compound 1, the cobalt(II) cations are octahedrally coordinated into discrete complexes by two terminal N-bonding thiocyanate anions, the N atoms of three pyridine-4-thioamide ligands and one acetonitrile molecule. Additional acetonitrile solvate molecules are located between the complexes. The complexes and solvate molecules are linked via intermolecular hydrogen bonding into a three-dimensional framework. In compound 2, the nickel(II) cations are likewise octahedrally coordinated by two terminal N-bonded thiocyanate anions and four N-bonding pyridine-4-thioamide ligands into discrete complexes. From their arrangement cavities are formed, in which the methanol solvate molecules are located. Again, the complexes and solvate molecules are linked into a three-dimensional framework by intermolecular hydrogen bonding. [ABSTRACT FROM AUTHOR]

The reaction of iron thiocyanate with 3-cyanopyridine (C6H4N2) leads to the formation of two compounds with the composition [Fe(NCS)2(C6H4N2)4] (1) and [Fe(NCS)2(C6H4N2)2(H2O)2]⋅2C6H4N2 (2). The asymmetric unit of 1 consists of one iron cation, two thiocyanate anions and four 3-cyanopyridine ligands in general positions. The iron cation is octahedrally coordinated by two N-bonded thiocyanate anions and four 3-cyanopyridine ligands. The complexes are arranged in columns along the crystallographic c-axis direction and are linked by weak C--H⋯N interactions. In 2, the asymmetric unit consists of one iron cation on a center of inversion as well as one thiocyanate anion, one 3-cyanopyridine ligand, one water ligand and one 3-cyanopyridine solvate molecule in general positions. The iron cation is octahedrally coordinated by two N-bonded thiocyanate anions, two cyanopyridine ligands and two water ligands. O--H⋯N and C--H⋯S hydrogen bonding is observed between the water ligands and the solvent 3-cyanopyridine molecules. In the crystal structure, alternating layers of the iron complexes and the solvated 3-cyanopyridine molecules are observed. Powder X-ray (PXRD) investigations reveal that both compounds were obtained as pure phases and from IR spectroscopic measurements conclusions on the coordination mode of the thiocanate anions and the cyanogroup were made. Thermogravimetric (TG) and differential thermoanalysis (DTA) of 1 indicate the formation of a compound with the composition {[Fe(NCS)2]3(C6H4N2)4}n that is isotypic to the corresponding Cd compound already reported in the literature. TG/DTA of 2 show several mass losses. The first mass loss corresponds to the removal of the two water ligands leading to the formation of 1, which transforms into {[Fe(NCS)2]3(C6H4N2)4}n, upon further heating. [ABSTRACT FROM AUTHOR]

The reaction of copper(I) bromide with 1,2-bis(pyridin-4-yl)ethene in acetonitrile leads to the formation of the title compound, {[CuBr(C12H10N2)]⋅-0.25C12H10N2}n or CuBr(4-bpe)⋅0.25(4-bpe) [4-bpe = 1,2-bis(pyridin-4-yl)-ethene]. The asymmetric unit consists of one copper(I) cation and one bromide anion in general positions as well as two crystallographically independent half 4-bpe ligands and a quarter of a disordered 4-bpe solvate molecule that are completed by centers of inversion. The copper(I) cations are tetrahededrally coordinated as CuBr2N2 and linked by pairs of μ-1,1-bridging bromide anions into centrosymmetric dinuclear units that are further connected into layers by the 4-bpe coligands. Between the layers, interlayer C--H⋯Br hydrogen bonding is observed. The layers are arranged in such a way that cavities are formed in which the disordered 4-bpe solvate molecules are located. Powder X-ray (PXRD) investigations reveal that a pure sample has been obtained. Thermogravimetric (TG) and differential thermoanalysis (DTA) measurements show two mass losses that are accompanied by endothermic events in the DTA curve. The first mass loss correspond to the removal of 0.75 4-bpe molecules, leading to the formation of (CuBr)2(4-bpe), already reported in the literature as proven by PXRD. [ABSTRACT FROM AUTHOR]

Reaction of Cd(NCS) 2 and Zn(NCS) 2 with the co-ligands 4-benzylpyridine or 4-benzoylpyridine leads to the formation of eight new compounds, of which one crystallizes in two polymorphic modifications. The co-ligand rich compounds with the composition M(NCS) 2 (L) 4 (M = Cd, Zn and L = 4-benzylpyridine or 4-benzoylpyridine) ( 1 ) form discrete complexes, in which the metal cations are each coordinated by four co-ligands and two N -bonded anionic ligands within slightly distorted octahedra. In the co-ligand deficient compounds ( 2 ) with the composition M(NCS) 2 (L) 2 two structure types are observed. The Zn compounds form discrete complexes in which the Zn cations are tetrahedral coordinated ( 2-Zn ), whereas in the Cd compounds ( 2-Cd ) the metal cations are octahedral coordinated and linked into chains by pairs of µ-1,3-bridging thiocyanate anions. Upon heating, compounds 1 loose half of the co-ligands and transform into compounds 2 . The coordination mode of the anionic ligands was also investigated by IR and Raman spectroscopy. All compounds show blue-green ligand-based luminescence with emission maxima varying between 21,857 cm −1 and 18,264 cm −1 . [ABSTRACT FROM AUTHOR]

The crystal structure of the title salt, (C6H8NO)8[Fe(NCS)4(C6H7NO)2]- [Fe(NCS)5(C6H7NO)]2[Fe(NCS)6], comprises three negatively charged octahedral FeIII complexes with different coordination environments in which the FeIII atoms are coordinated by a different number of thiocyanate anions and 4-methoxypyridine ligands. Charge balance is achieved by 4-methoxypyridinium cations. The asymmetric unit consists of three FeIII cations, one of which is located on a centre of inversion, one on a twofold rotation axis and one in a general position, and ten thiocyanate anions, two 4-methoxypyridine ligands and 4-methoxypyridinium cations (one of which is disordered over two sets of sites). Beside to Coulombic interactions between organic cations and the ferrate(III) anions, weak N--H...S hydrogen-bonding interactions involving the pyridinium N--H groups of the cations and the thiocyanate S atoms of the complex anions are mainly responsible for the cohesion of the crystal structure. [ABSTRACT FROM AUTHOR]

Reaction of Cd(NCS)2 and Zn(NCS)2 with 3-ethylpyridine leads to the formation of compounds of compositions M(NCS)2(3-ethylpyridine)4 (M=Cd, 1-Cd; Zn, 1-Zn) and M(NCS)2(3-ethylpyridine)2 (M=Cd, 2-Cd; Zn, 2-Zn). 1-Cd and 1-Zn are isotypic and form discrete complexes in which the metal cations are octahedrally coordinated by two trans-coordinating N-bonded thiocyanate anions and four 3-ethylpyridine co-ligands. In 2-Cd the cations are also octahedrally coordinated but linked into chains by pairs of μ-1,3-bridging anionic ligands. 2-Zn is built up of discrete complexes, in which the Zn cation is tetrahedrally coordinated by two N-bonded thiocyanate anions and two 3-ethylpyridine co-ligands. Compounds 1-Cd, 2-Cd and 2-Zn can be prepared in a pure state, whereas 1-Zn is unstable and transforms on storage into 2-Zn. If 1-Cd and 1-Zn are heated, a transformation into 2-Cd, respectively 2-Zn is observed. Luminescence measurements reveal that 1-Cd, 2-Cd and 2-Zn emit light in the blue spectral range with maxima at, respectively, 21724, 21654 and 22055 cm−1, assigned to ligand-based luminescence. [ABSTRACT FROM AUTHOR]

Reaction of Co(NCS)2 and Zn(NCS)2 with 4-pyridinethioamide led to the formation of compounds with composition [Co(NCS)2(C6H6N2S)4].H2O (1) and [Zn(NCS)2(C6H6N2S)2] (2), respectively. The asymmetric unit of compound 1, consists of one cobalt(II) cation, two thiocyanate anions, four 4-pyridinethioamide ligands and one water molecule whereas that of compound 2 comprises one zinc(II) cation that is located on a twofold rotation axis as well as one thiocyanate anion and one 4-pyridinethioamide ligand in general positions. In the structure of compound 1, the cobalt(II) cations are octahedrally coordinated by two terminal N-bonding thiocyanate anions and by the N atoms of four 4-pyridinethioamide ligands, resulting in discrete and slightly distorted octahedral complexes. These complexes are linked into a three-dimensional network via intermolecular N--H. . .S hydrogen bonding between the amino H atoms and the thiocyanate S atoms. From this arrangement, channels are formed in which the water molecules are embedded and linked to the host structure by intermolecular O--H. . .S and N--H. . .O hydrogen bonding. In the structure of compound 2, the zinc(II) cations are tetrahedrally coordinated by two Nbonding thiocyanate anions and the N atoms of two 4-pyridinethioamide ligands into discrete complexes. These complexes are likewise connected into a threedimensional network by intermolecular N--H. . .S hydrogen bonding between the amino H atoms and the thioamide S atoms. [ABSTRACT FROM AUTHOR]

The crystal structures of the title salts, (C7H11 N2 )2 [Mn(NCS)4] (1) and (C7H11 N2 )3[Mn(NCS)5] (2), consist of manganese(II) cations that are tetrahedrally (1) or trigonal-bipyramidally (2) coordinated to four or five terminal Nbonded thiocyanate ligands, respectively, into discrete anionic complexes. The negative charge is compensated by two (1) or three (2) 4-(dimethylamino)-pyridinium cations, which are protonated at the pyridine N atom. The asymmetric unit of compound 1 consists of one anionic complex and two 4-(dimethylamino)pyridinium cations, whereas that of compound 2 consists of two anionic complexes and six 4-(dimethylamino)pyridinium cations, all of them located in general positions. These complexes are linked by N-H…S, C-H…S and C-H…N hydrogen-bonding interactions between the 4-(dimethylamino) pyridinium cations and the thiocyanate ligands into three-dimensional network structures. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, [Co(NCS)2(C6H6NS)4]·CH3OH, consists of one cobalt(II) cation, two thio­cyanate anions, four pyridine-4-carbo­thio­amide ligands and one methanol mol­ecule that are located in general positions. The CoII cations are coordinated by two terminal N-bonding thio­cyanate anions and four N-bonding pyridine-4-carbo­thio­amide ligands, resulting in discrete and slightly distorted octa­hedral complexes. These complexes are linked into a three-dimensional network via inter­molecular N—H···S hydrogen bonding between the amino H atoms and the thio­cyanate and pyridine-4-carbo­thio­amide S atoms. From this arrangement, channels are formed in which the methanol solvate mol­ecules are embedded and linked to the host structure by inter­molecular O—H···S and N—H···O hydrogen bonding. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, [Fe(NCS)2(C6H4N2)2(H2O)2]·2C6H4N2, comprises one FeII cation occupying an inversion centre as well as one thiocyanate anion, one water molecule and two 4-cyanopyridine molecules in general positions. The iron cations are coordinated by two N-bonded thiocyanate anions, two (pyridine)N-bonded 4-cyanopyridine ligands and two water molecules into discrete complexes. The resulting coordination polyhedron can be described as a slightly distorted octahedron. The discrete complexes are connected through centrosymmetric pairs of (pyridine)C--H...N(cyano) hydrogen bonds into chains that are further linked into a three-dimensional network through intermolecular O--H...N hydrogen bonds involving the 4-cyanopyridine solvent molecules. [ABSTRACT FROM AUTHOR]

Several coordination compounds, based on Cd halides and 2-methylpyrazine (Mepyz) or 2-chloropyrazine (Clpyz) as N-donor coligands, are synthesized and their crystal structures determined by either single-crystal or X-ray powder diffraction (XRPD). In [CdX2(2-Clpyz)2]n (X = Cl: 1-Cl-Clpyz; X = Br: 1-Br-Clpyz; and X = I: 1-I-Clpyz) and [CdX2(2-Mepyz)2]n (X = Cl: 1-Cl-Mepyz; X = Br: 1-Br-Mepyz; and X = I: 1-I-Mepyz), the Cd cations are octahedrally coordinated by two N-donor ligands and are linked into chains by the halide anions that share common edges. In the ligand-deficient compounds [CdX2(2-methylpyrazine)] n (X = Cl: 2-Cl-Mepyz; X = Br: 2-Br-Mepyz; and X = I: 2-I-Mepyz), similar CdX2 chains, which are connected into layers by the N-donor ligands, are observed. Thermal analysis of all 1-Mepyz compounds shows a transformation into 2-Mepyz, which is not observed for the 2-chloropyrazine compounds. On further heating, compounds of composition [(CdX2)2(2-Mepyz)]n (X = Cl: 3-Cl-Mepyz; X = Br: 3-Br-Mepyz) and [(CdI2)3(2-Mepyz)2] (4-I-Mepyz) are observed. A discrete complex, with the composition CdI2(2-Mepyz)2 monohydrate (1-I-Mepyz-H2O), and a hydrate with the composition [(CdI2)(2-Mepyz)]·1.5H2O (2-IMepyz-H2O) with an unknown structure, were also synthesized. Both lose the water molecules upon heating. Luminescence measurements show blue to orange emissions in the range of ca. 22530-16276 cm-1, depending on the halide or pyrazine substituent, as well as the metal halide/ligand ratio. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title complex, [Co(NCS)2(C7H9N)2(CH3OH)2], comprises of one CoII cation located on a centre of inversion, one thiocyanate ligand, one methanol ligand and one 3,5-dimethylpyridine ligand. The CoII cation is octahedrally coordinated by two terminal N-bonding thiocyanate anions, two methanol molecules and two 3,5-dimethylpyridine ligands into a discrete complex. The complex molecules are linked by intermolecular O--H⋯S hydrogen bonding into chains that elongate in the direction parallel to the b axis. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, [Ni(NCS)2(C5H4ClN)2(H2O)2], consists of one nickel(II) cation that is located on a center of inversion and one thiocyanate anion, one water molecule and one 2-chloropyridine ligand all occupying general positions. The NiII cation is octahedrally coordinated by two terminal N-bound thiocyanato ligands, two aqua ligands and two N-bound 2- chloropyridine ligands into discrete complexes. Individual complexes are linked by intermolecular O--H...S and O--H...Cl hydrogen-bonding interactions into a layered network extending parallel to the bc plane. Weak interactions of types C--H...S and C--H...Cl consolidate the crystal packing. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, [Co(NCS)2(C6H6N2O)3(H2O)]·-2.5H2O, comprises one CoII cation, three isonicotinamide ligands, two thiocyanate anions, one aqua ligand and two water solvent molecules in general positions, as well as one water solvent molecule that is located on a twofold rotation axis. The CoII cations are octahedrally coordinated by two terminally N-bonded thiocyanate anions, one water molecule and three isonicotinamide ligands, each coordinating via the pyridine N atom. The discrete complexes are linked by intermolecular O-H...O, N-H...O and N-H...S hydrogen bonding into a three-dimensional network that contains cavities in which the solvent water molecules are located. The latter are linked by further O-H...O hydrogen bonds to the network. There are additional short contacts present in the crystal, indicative of weak C-H...S, C-H...O and C-H...N interactions. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, [Co(NCS)2(C6H6N2O)4]⋅2C6H6-N2O⋅C2H5OH, comprises one CoII cation, two thiocyanate anions, four coordinating and two solvent isonicotinamide molecules and one ethanol solvent molecule. The CoII cations are octahedrally coordinated by four N-coordinating isonicotinamide ligands and two terminally N-bonded thiocyanate anions. These discrete complexes are linked by intermolecular N-H⋯O and N-H⋯S hydrogen-bonding interactions into a three-dimensional network. The two isonicotinamide and the ethanol solvent molecules are embedded in channels of this network and are linked through further N-H-⋯O and N-H-⋯N hydrogen bonds to the network. The ethanol solvent molecule is disordered over two sets of sites (occupancy ratio 0.6:0.4). [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title complex, [Zn(SCN)2(C6H6N2O)2], consists of one Zn2+ cation located on a twofold rotation axis, as well as of one thiocyanate anion and one neutral isonicotinamide ligand, both occupying general positions. The Zn2+ cation is tetrahedrally coordinated into a discrete complex by the N atoms of two symmetry-related thiocyanate anions and by the pyridine N atoms of two isonicotinamide ligands. The complexes are linked by intermolecular C-- H⋯O and N--H⋯O, and weak intermolecular N--H⋯S hydrogen-bonding interactions into a three-dimensional network. [ABSTRACT FROM AUTHOR]

Two polymorphic modifications of 1,4-dibromo-2,5-bis(bromomethyl)benzene have been discovered and structurally characterized; their thermodynamic relationships and transformation behaviour have been investigated. Form I crystallizes in the triclinic space group P1̅, whereas form II crystallizes monoclinic in space group P21/c, both with imposed inversion symmetry of the molecule. Their crystal structures involve layers, in which the molecules are linked by intermolecular Br…Br interactions to form similar systems of linked rings. Initial studies involved batches consisting of pure form I or a mixture of I with traces of II (as obtained by chance from the synthesis), but solvent-mediated conversion experiments in various solvents clearly prove that form II is the thermodynamically stable form at room temperature. Thermomicroscopic and heating-rate-dependent DSC measurements show that the melting point of form I is slightly higher than that of form II and that the higher melting polymorph exhibits the lower heat of fusion. Therefore, form I becomes thermodynamically stable at higher temperatures and both forms are related by enantiotropism. This is also in agreement with the density rule, because the low-temperature form II exhibits the higher density. Isothermal annealing of both modifications at different temperatures reveals a thermodynamic transition temperature of about 135 °C, which is in excellent agreement with that of 137.5 °C calculated from the melting temperatures and the heat of fusion of both forms. The high-temperature form can easily be prepared pure by solidification of the melt, which is in agreement with Ostwald's step rule, because form I crystallizes at a temperature where it is thermodynamically metastable. A qualitative energy/temperature diagram is presented. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the polymeric title compound, {[Cd(NCS)2(C6H6-N2S)]2CH3OH}n, consists of one cadmium(II) cation that is located on a centre of inversion as well as one thiocyanate anion, one pyridine-4-carbothioamide ligand and one methanol molecule in general positions. The CdII cations are octahedrally coordinated by the pyridine N atom of two pyridine-4-carbothioamide ligands and by the S and N atoms of four thiocyanate anions and are linked into chains along [010] by pairs of anionic ligands. These chains are further linked into layers extending along (201) by intermolecular N-H···O and O-H···S hydrogen bonds. One of the amino H atoms of the pyridine-4-carbothioamide ligand is hydrogen-bonded to the O atom of a methanol molecule, and a symmetry-related methanol molecule is the donor group to the S atom of another pyridine-4-carbothioamide ligand whereby each of the pyridine-4-carbothioamide ligands forms two pairs of centrosymmetric N-H···S and O-H···S hydrogen bonds. The methanol molecules are equally disordered over two orientations. [ABSTRACT FROM AUTHOR]