Search

Single crystals of Rb2H2P2O6·2H2O could be obtained from aqueous solutions of hypodiphosphoric acid and rubidium carbonate. Its crystal structure was determined by X-ray diffraction and it crystallizes in the monoclinic space group P21/c with Z = 4. The salt-like title compound consists of [H2P2O6]2– units in staggered P2O6-skeleton conformation, Rb+ cations, and H2O molecules, held together by intermolecular hydrogen bonds of the type O···O. The vibrational spectra (IR/FIR and Raman) of the rubidium salt were recorded and an assignment of the vibrational modes is proposed based on the point group C2h for the P2O6-skeleton of the anion. The thermal behavior of Rb2H2P2O6·2H2O is dominated by a complex TG decay indicating a simultaneous H2O delivery coupled with a disproportionation of [H2P2O6]2–, what is also supported by Raman spectra of heated samples.

Single crystals of the alkali-metal hypodiphosphates K4P2O6·8H2O (1) and Na2K2P2O6·8H2O (2) could be obtained and their crystal structures determined. The compounds 1 and 2 crystallize isotypic in the orthorhombic space group Pbca (no. 61) with four formula units in the unit cell. The crystal structures are built up by discrete [P2O6]4– units in an ethane-like staggered conformation, by the corresponding alkali-metal cations and water molecules. FT-IR/FIR and FT-Raman spectra of the crystalline title compounds were recorded and a complete assignment for the [P2O6]4– modes is proposed. Raman spectra of aqueous hypodiphosphate solutions deliver additional polarization data supporting the band assignment. Compounds 1 and 2 show a complete H2O loss in case of slow heating avoiding the formation of a hydrate melt.

1-Butyl-4-methylpyridinium hexachloridotantalate(V), [BMPy][TaCl6] (1), tetrakis(1-butyl-4-methylpyridinium) bis(hexachloridotantalate(V) (μ-oxido)-decachloridotantalate(V), [BMPy]4[(TaCl6)2(Ta2OCl10)] (2), and bis(1-ethyl-3-methylimidazolium)-(μ-oxido)-decachloridoditantalate(V), [EMIm]2[Ta2OCl10] (3) were synthesized and characterized by single-crystal X-ray diffraction and vibrational spectroscopy. Compounds 1 and 3 crystallize in the monoclinic space group P21/c (no. 14), whereas compound 2 crystallizes in the triclinic space group P (no. 2). All compounds are built up by the mentioned bulky organic cations and octahedral [TaCl6]– respective linear [Ta2OCl10]2– anions. Coulomb interactions are dominant between the ionic species. FT-IR and FT-Raman spectra were recorded and interpreted, especially with respect to the inorganic species [TaCl6]– (Oh) and [Ta2OCl10]2– (Ci symmetry, approximately D4h). The melting temperatures of compounds 1–3 are given.

Single crystals of 2,3,5-triphenyltetrazolium hexachloroniobate(V), [TPT] [NbCl6], (1) and of 2,3,5-triphenyltetrazolium oxotetrachloroniobate(V), [TPT] [NbOCl4(CH3CN)], (2) could be obtained and their crystal structures determined. The yellow compound 1 crystallizes in the monoclinic space group P21/c (C2h5, no. 14) with a = 1321.6(3), b = 1080.7(2), c = 1740.2(4) pm, β = 111.54(2)°, and Z = 4. Its structure is isotypic to that of the recently characterized [TPT] [SbCl6] and built up by [TPT]+ cations and octahedral [NbCl6]– anions. The light yellow compound 2 crystallizes in the orthorhombic space group Pbcm (D2h11, no. 57) with a = 1574.4(1), b = 1047.7(1), c = 1723.4(1) pm, and Z = 4. The ionic compound contains [TPT]+ cations and [NbOCl4(CH3CN)]– anions. The nitrogen atom of the acetonitrile solvate molecule is coordinated to the niobium ion in the trans-position to the oxo ligand. The Nb−O bond length of 169.6 pm corresponds to a double bond. The [TPT] [NbOCl4(CH3CN)] formation proceeds with the hydrate [TPT]Cl  H2O obvious via NbOCl3. The FT-Raman and FT-IR/FIR spectra of both compounds have been recorded and interpreted, especially with respect to the inorganic structure parts. The melting temperatures of 1 and 2 are given.

2,3,5-Triphenyltetrazolium hexachlorophosphate, [C19H15N4]+[PCl6]−, [TPT]+[PCl6]− (1), and 2,3,5-triphenyltetrazolium dichlorophosphate(V), [C19H15N4]+[PO2Cl2]−, [TPT]+[PO2Cl2]− (2), were synthesized by reactions of anhydrous 2,3,5-triphenyltetrazolium chloride, [TPT]+Cl−, and 2,3,5-triphenyltetrazolium chloride monohydrate [TPT]+Cl− ・H2O, with PCl5 in dry acetonitrile, and their crystal structures were determined by single-crystal X-ray diffraction analysis. In the title compounds, the [TPT]+ cations show a face-to-face stacked orientation between the phenyl rings of neighboring molecules, which is caused by intermolecular π ・ ・ ・π interactions. The crystal structure of compound 1 consists of layers of 2,3,5-triphenyltetrazolium cations and hexachlorophosphate anions. In compound 2 the tetrahedral [PO2Cl2]− anions exhibit approximate C2v symmetry with P-O bond lengths from 1.454 to 1.463 Å and P-Cl bond lengths from 2.038 to 2.050 Å . The Raman spectrum of compound 1 was recorded, and the assignment of the [PCl6]− Raman modes is proposed.

Single crystals of 2,3,5-triphenyltetrazolium hexachloroantimonate(V), [TPT][SbCl6] (1) and of 1-ethyl-3-methyl-4-chloroimidazolium hexachloroantimonate(V), [Cl-EMIm][SbCl6] (2) could be obtained and their crystal structures determined. Compound 1 crystallizes in the monoclinic space group P21/c (C2h5) with a = 1328.7(2), b = 1085.2(1), c = 1752.4(3) pm, β = 111.51(1)°, and Z = 4, whereas compound 2 crystallizes in the same monoclinic space group P21/c (C2h5) with a = 716.9(1), b = 1378.0(3), c = 1589.5(2) pm, β = 97.61(1)°, and Z = 4. The compound 1 is composed of a pair of ions, the 2,3,5-triphenyltetrazolium cation and the hexachloroantimonate(V) anion. 2 is an ionic 1:1 compound with 1-ethyl-3-methyl-4-chloroimidazolium cations, formed by chlorination of [EMIm]+ by SbCl5 and hexachloroantimonate(V) anions. The FT-Raman spectra of the title compounds have been recorded and interpreted, especially with respect to the inorganic part respective to the [SbCl6]–.

Bis(1,3-dimethylimidazolium methylsulfate) [18-crown-6] (1), ([DMIm]2[CH3SO4]2[18-crown-6], bis(1-butyl-3-methylimidazolium methylsulfate) [18-crown-6] (2), ([BMIm]2[CH3SO4]2[18-crown-6]), bis(1-ethyl-3-methylimidazolium methanesulfonate) [18-crown-6] (3), ([EMIm]2 [CH3SO3]2[18-crown-6]) and bis(1-ethyl-3-methylimidazolium trifluoromethanesulfonate) [18-crown-6] (4), ([EMIm]2[CF3SO3]2[18-crown-6]) were prepared and characterized by single-crystal X-ray diffraction, NMR and Raman spectroscopy. Coulomb interactions between the ionic (liquid) components as well as hydrogen bonding are important. No significant close contacts are observed between the ionic components and the 18-crown-6 molecules. Crystal structures of all compounds consist of alternated layers of crown-ether molecules and respective ionic units compounds. Within the layers of the ionic components (compounds 1, 3 and 4), two cations are linked to each other by C–H⋯π interactions between one methyl carbon and the imidazolium ring of another cation.

Single crystals of (NH4)4P2S6 ・ 2H2O could be obtained and the crystal structure determined (monoclinic, P21/c with a = 6.931(1), b = 12.730(2), c = 17.446(2) Å , β = 96.87(1)°, V = 1528.2(4) Å3, Z = 4). The NH4 +, and [P2S6]4− ions and the water molecules are involved in an extended hydrogenbonding network. The FT-Raman and FT-IR spectra have been recorded and the observed vibrational frequencies assigned to tetrahedral NH4 + and [P2S6]4− (D3d) ions as well as to H2O molecules. The thermogravimetric analysis has shown that (NH4)4P2S6 · 2H2O starts to decompose at around 60 °C (up to 170 °C), but no distinct intermediates could be observed.

The thermal decomposition of Ni(NO3)2·6H2O (1), Ca(NO3)2·4H2O (2) and nitryl/nitrosyl nitrato nickelate(II), NO2/NO[Ni(NO3)3] (3), was investigated by thermogravimetric measurements with quasi-isothermal conditions and compared to Co(NO3)2·6H2O. The respective decomposition processes of 1 and 2 differ from each other showing that at one hand anhydrous Ca(NO3)2 was obtained whereas anhydrous nickel dinitrate has not be formed due to redox and condensation reactions. Instead basic nickel compounds have been formed. In reducing atmosphere nickel metal can be obtained. Anhydrous Ni(NO3)2 results by the thermal degradation of nitryl/nitrosyl nitrato nickelate. FT-Raman spectra have been of help in the judgement of the decomposition processes.

Single crystals of rubidium hexathiodiphosphate(V), Rb2P2S6, have been obtained and investigated by single crystal X-ray diffraction, and IR/FIR and Raman spectroscopy. The title compound crystallizes isotypically to the potassium, caesium and thallium analogues in the orthorhombic space group Immm (no. 71) with a = 8.485(3), b= 6.953(3), c =9.259(3 Å , and Z = 2, final R1= 0.0579 and wR2 = 0.0987. The crystal structure is characterized by discrete [P2S6]2− anions (edge-sharing double-tetrahedra) with D2h symmetry. Rubidium is coordinated by ten sulfur atoms forming a slightly distorted two-capped tetragonal prism with a coordination number CNRb 10. The FT-Raman and FT-IR/FIR spectra have been recorded and a factor group analysis was carried out.

The potassium crown-ether thiophosphate, [K(18-crown-6)]2 [P2S6]·2 CH3CN, has been obtained by the reaction of K2P2S6 with 18-crown-6 in acetonitrile. The title compound adopts a molecular array of [K(18-crown-6)]2 [P2S6] wherein two K(18-crown-6) units are linked by the P2S6 group. FT-Raman and FT-IR spectra of the title compound have been recorded and interpreted, especially with respect to the P2S6 group and in comparison to the few known metal meta-thiodiphosphates.

The thermal decomposition of Co(NO3)2·6H2O (1) as well as that one of NO[Co(NO3)3] (Co(NO3)2·N2O4) (2) was followed by thermogravimetric (TG) measurements, X-ray recording and Raman and IR spectra. The stepwise decomposition reactions of 1 and 2 leading to anhydrous cobalt(II)nitrate (3) were established. In N2 atmosphere, cobalt oxides are finally formed whereas in H2/N2 (10% H2) cobalt metal is produced. Rapid heating of cobalt(II)nitrate hexahydrate causes melting (formation of a hydrate melt) and therefore side reactions in the hydrate melt by incoupled reactions and evolution/evaporation of different species as, e.g., HNO3, NO2, etc. In case of larger amounts in dense packing in the sample container, the formation of oxo(hydoxo)nitrates is possible at higher temperature. For 2, its thermal decomposition to 3 was followed and its decomposition mechanism is proposed.

Cobalt orotate trihydrate, [Co(C5N2O4H2)]·3H2O, has been synthesized and its crystal structure determined. The title compound crystallizes in the orthorhombic space group P212121 (no. 19) with a = 771.5(2), b = 788.9(7), c = 1470.4(2) pm, and Z = 4. Bridging orotate anions coordinate in a mono- and bidentate manner to the Co atom resulting in infinite chains of alternating Co(II) cations and orotate (OrH2−) anions parallel to the c axis. The distorted octahedral Co coordination geometry is completed by three H2 molecules. The FT-Raman and FT-IR spectra of the crystalline compound have been recorded and an assignment of the vibrational modes is proposed. The thermal behavior (TG) was investigated.

Single crystals of Rb2H2P2O6·2H2O are obtained from an equimolar aqueous solution of H4P2O6 and Rb2CO3 at 4 °C.

[Ph4P]2[Bi2Br8(CH3COCH3)2] (1) was obtained by the reaction of [Ph4P]Br and BiBr3 in acetone. Single crystals were grown by allowing a layer of n-hexane to diffuse into the acetonic solution of 1. The crystal structure was determined by means of X-ray diffraction. 1 crystallises with monoclinic symmetry in the space group P21/n, No. 14 with the lattice parameters: a = 13.358(2), b = 12.637(2), c = 18.565(3) A, β = 102.62(1)°, V = 3058.1(8) A3 and Z = 4. The structure is characterised by the anion [Bi2Br8(CH3COCH3)2]2– which is embedded in a matrix of [Ph4P]+ cations. The anion can be described as two edge-sharing square pyramids with the apical bromide ions in anti-position. Acetone co-ordinates the bismuth atoms via oxygen atoms and increases the co-ordination number of central bismuth atoms to six which results in the formation of a distorted bi-octahedron. The distortion is due to the difference in terminal and bridging Bi–Br bond lengths. FT-IR and Raman spectroscopic data are presented. In addition, the thermal behaviour of the compound was studied with the aid of TG/DSC coupled with MS revealing that acetone leaves the crystal in two steps. The compound melts at 203 °C and transforms into a glass on cooling. Synthese, Kristallstruktur, Schwingungsspektren und thermisches Verhalten von [Ph4P]2[Bi2(μ-Br)2Br6 (CH3COCH3)2] [Ph4P]2[Bi2Br8(CH3COCH3)2] (1) wurde durch Reaktion von [Ph4P]Br mit BiBr3 in Aceton synthetisiert. Zur Strukturbestimmung geeignete Einkristalle konnten durch Diffusion einer n-Hexan Schicht in die Acetonlosung von 1 gewonnen werden. 1 kristallisiert mit monokliner Symmetrie in der Raumgruppe P21/n, No. 14 mit den Gitterkonstanten: a = 13,358(2), b = 12,637(2), c = 18,565(3) A, β = 102,62(1)°, V = 3058,1(8) A3 und Z = 4. Die Struktur wird durch das Anion [Bi2Br8(CH3COCH3)2]2– charakterisiert, dass in eine Matrix von [Ph4P]+-Kationen eingebettet ist. Das Anion besteht aus zwei kantenverknupften quadratischen Pyramiden mit den apicalen Bromid-Ionen in Antiposition. Aceton ist an Wismut uber Sauerstoffatome gebunden, wodurch sich die Koordinationszahl von Wismut auf sechs erhoht und sich ein verzerrtes Bi-oktaeder bildet. Die Verzerrung wird durch die unterschiedlichen Abstande von Wismut zu terminalen und verbruckenden Bromatomen hervorgerufen. FT-IR- und Raman-spektroskopische Daten werden gegeben. Das thermische Verhalten der Verbindung wurde mit Hilfe einer TG/DSC-MS-Kopplung untersucht. Aceton wird in zwei Schritten abgegeben. Die Verbindung schmilzt bei 203 °C und erstarrt beim Abkuhlen als Glas.

Several preparative routes to bis(n-alkanethiolato)mercury(II) compounds of the general composition Hg(SCnH2n+1)2 for n = 1−10, 12 (compounds 1−11, respectively) are presented, including the reacti...

The preparation of long-chain symmetric di-n-alkyl disulfides based on the reaction of BUNTE SALTS (RS2O3Na) with iodine is reported. 1H-NMR, FT-IR, and FT-RAMAN spectra of the solid and liquid/molten aliphatic title disulfides were recorded. An assignment of the vibrational frequencies is proposed especially in regard to the S-S and C-S vibrations. Distinct spectral differences are determined between the solid and liquid state, as well as between disulfides with even and those with odd numbered alkyl substituents, respectively. The observed phenomena are ascribed to different species in the solids and liquids/melts and their respective VAN DER WAALS interactions. In addition, mass spectra, GC-MS studies, as well as the thermal behaviour of the disulfides, based on investigations by DSC and TGA, are reported.

Vibrational spectra are presented for Tl 2 P 2 S 6− x Se x and Ag 2 P 2 S 6− x Se x ( x =0–6) reaction mixtures. Reaction charges with high selenium contents gave glassy products in which the main building units appear to be the hexaselenidometadiphosphate anion, P 2 Se 6 2− . For intermediate x values mixed thio–seleno–metadiphosphates are formed. Geometry and equilibrium energy are calculated and the vibrational spectrum of the P 2 Se 6 2− anion is well modelled by ab initio quantum chemical calculations. For the probably microcrystalline Tl 2 P 2 S 6− x Se x series, Se seems to first enter the terminal positions of the anions. According to the calculations, bridged selenium and terminal sulfur are favored in mixed P 2 S 6− x Se x 2− anions, and the spectra seem to verify this for the Ag 2 P 2 S 6− x Se x series. No evidence for monomeric PSe 3 − was found.

The condensed phase and matrix isolation IR and Raman spectra of antimony tribromide are reported. The solid-state spectrum comprises bands assignable to both molecular SbBr 3 and ionic SbBr 6 − species. The frequency shifts and mode sequence in the melt spectrum indicate strong dipole-dipole interactions. The matrix isolation spectra show bands of monomeric SbBr 3 and of its centrosymmetric dimer, but no features of cooperative interactions. A “bond fluctuation” explanation, previously forwarded for antimony trichloride, is considered to be further substantiated by the present findings.

Single crystals of K4P2O6·8H2O and Na2K2P2O6·8H2O are prepared by addition of KOH to an aqueous solution of hypodiphosphoric acid (20 °C) resp.

High-resolution FT-Raman spectra including solution spectra with polarization measurements, as well as IR spectra of highly purified and analyzed C 60 and C 70 samples were recorded. Semi-empirical Parametric Method 3 (PM3) calculations of all C 60 and C 70 vibrational frequencies were performed. Based on all experimental spectroscopic results, selection rules, PM3 results and computer visualized normal modes of vibration, a correlation, in the sense of a genetic relationship, between C 60 and C 70 vibrations is developed. For the intrinsic C 60 vibrations only one H g mode remains to be assigned tentatively. A complete assignment for all intrinsic C 70 frequencies is proposed. With quite a few exceptions, caused by peculiarities of vibrations of the C 60 and C 70 cluster molecules, observed and calculated vibrational frequencies correlate very well. It is concluded that all cluster vibrations cannot be modeled uniformly.

C{sub 60}/C{sub 70} containing soot was produced by arc vaporization of graphite. The chromatographic separation of soot yielded fairly pure C{sub 60} and C{sub 70} samples. High-resolution FT-Raman spectra of C{sub 60} and C{sub 70} specimen as well as C{sub 60} and C{sub 70} solutions including polarization measurements are recorded. Compared to the spectrum of solid C{sub 60}, some Raman bands of the C{sub 60} solution change their position and shape. Even the purest commercial C{sub 60} samples contain solvent inclusions (impurities) in the order of some percentage. The chromatographic separation combined with Raman polarization measurements of solutions allows an evaluation of the fundamental vibrations of the C{sub 60} molecule. Its assignment, in accordance with the group theoretical expectation, is proposed. The existence of small amounts of C{sub 60} isomers (symmetry e.g., C{sub 2v}, D{sub 2h}, D{sub 2d}) in icosahedral C{sub 60} (I{sub h}) is affirmed based on the polarization measurements. For C{sub 70} the most extended set of Raman frequencies is presented. 40 refs., 14 figs., 2 tabs.

TlEu[PS4] was synthesized from the elements in a sealed quartz ampoule at 1 150 K. The compound forms transparent orange needles, stable in air and moisture. It crystallizes in the orthorhombic system, space group Pnma (No. 62), with cell dimensions a = 12.157(2), b = 6.581(1), c = 8.802(2) A, Z = 4. The crystal structure consists of discrete [PS4]3− anions interconnected by Tl+ and Eu2+. The tetrahedral [PS4]3− groups are slightly distorted with PS bond lengths in the range 2.028 to 2.043 A. These tetrahedral anions are arranged in such a way that the sulfur atoms form columns of distorted trigonal S6 prisms along [0 0 1]. The columns are condensed via common edges to puckered layers parallel to (1 0 0). The interlayer region consists of empty distorted half-cubes and tetrahedral holes, half of them filled by P atoms. The trigonal prisms in the columns are centered alternately by Tl+ and Eu2+. In this way, the structure can be regarded as an ordered superstructure of the InNi2 type, where half of the tetrahedral holes are filled by phosphorus atoms: InInNi4□ ≙ TlEuS4P□. TlEu[PS4] is a centrosymmetric variant of the TlSn[PS4] structure type (space group Pna21). The vibrational spectrum is in accordance with the X-ray crystal structure, the Raman and infrared vibrations are assigned on the basis of [PS4]3− units with C2v symmetry. Kristallstruktur und Schwingungsspektrum von Thallium(I)-Europium(II)-tetrathiophosphat(V), TlEu[PS4] TlEu[PS4] wurde aus den Elementen bei 1 150 K in einer evakuierten Quarzampulle dargestellt. Die Verbindung bildet transparente, orangefarbene, luft- und feuchtigkeitsbestandige Nadeln, die orthorhombisch, Pnma (Nr. 62) mit a = 12,157(2), b = 6,581(1), c = 8,802(2) A, Z = 4 kristallisieren. Charakteristisch sind diskrete [PS4]3−-Anionen, die durch Tl+ und Eu2+ verbunden sind. Sie sind verzerrt tetraedrisch mit PS-Abstanden zwischen 2,028 und 2,043 A und so angeordnet, das Liganden benachbarter Gruppen trigonale S6-Prismen bilden, entlang [0 0 1] zu Saulen verknupft, die parallel (1 0 0) uber gemeinsame Kanten zu gewellten Schichten kondensiert sind. Dazwischen sind leere, verzerrte Halbwurfel und zur Halfte mit P-Atomen besetzte Tetraederlucken Durch die alternierende Besetzung mit Tl+ und Eu2+ sind diese Prismen leicht verzerrt. Man kann daher diese Struktur als eine geordnete, teilweise aufgefullte Uberstruktur des InNi2-Typs auffassen (InInNi4□ ≙ TlEuS4P□), aber auch als zentrosymmetrische Variante der TlSn[PS4]-Struktur (Raumgruppe Pna21). Das Schwingungsspektrum entspricht der Strukturbestimmung, die beobachteten Raman- und Infrarotbanden lassen sich zwanglos auf der Basis von [PS4]3− -Einheiten mit C2v-Symmetrie zuordnen.

K2Mn[P2S6] was synthesized from the elements in sealed quartz ampoules at 1 173 K. The compound forms transparent light brown crystals, stable against air and moisture. The crystal structure (monoclinic; space group P21/n, No. 14; a = 6.1966(9), b = 12.133(2), c = 7.424(1) A, β = 101.52(1)°, Z = 2; Pearson code mP22) consists of columns of face-sharing S6 polyhedra (distorted octahedra and trigonal antiprisms) parallel to the a axis, interconnected by inserted K+ (CN 10; d(KS) = 3.23–3.92 A). The S6 polyhedra of the columns are centered alternately by Mn (in octahedra with d(MnS) = 2.647 A) and P2 pairs (in trigonal antiprisms) which are inclined to the a axis by 73.1°. The bond lengths in the resulting hexathiodiphosphate(IV) anions, [P2S6]4−, with approximate 3 2/m–D3d symmetry, are d(PP) = 2.211 A and d(PS) = 2.018 A. K2Mn[P2S6] is isotypic to K2Fe[P2S6], being the second member of this structure type. The internal modes of the observed Raman and FIR/IR spectra of K2Mn[P2S6] are in accord with the factor group analysis, and the fundamentals are assigned on the basis of [P2S6]4− units, taking into account the deviation of the D3d symmetry. Kristallstruktur und Schwingungsspektrum von Dikaliummangan(II)-hexathiodiphosphat(IV), K2Mn[P2S6] K2Mn[P2S6] wurde aus den Elementen bei 1 173 K in evakuierten Quarzampullen dargestellt. Die Verbindung bildet transparente, hellbraune, luft- und feuchtigkeits-bestandige Kristalle. Die Kristallstruktur von K2Mn[P2S6] (monoklin; Raumgruppe P21/n, No. 14; a = 6,1966(9), b = 12,133(2), c = 7,424(1) A, β = 101,52(1)°; Z = 2; Pearson-Code mP22) enthalt Saulen flachenverknupfter S6-Polyeder (verzerrte Oktaeder und trigonale Antiprismen), die parallel zur a-Achse verlaufen und durch K+ (KZ 10; d(KS) = 3,23–3,92 A) miteinander verbunden sind. Die S6-Polyeder der Saulen werden alternierend durch Mn (in Oktaedern mit d(MnS) = 2,647 A) bzw. P2-Paare (in trigonalen Antiprismen) zentriert, die zur a-Achse um 73,1° geneigt sind. Die Bindungslangen in den Hexathiodiphosphat(IV)-Anionen [P2S6]4− mit angenaherter 3 2/m–D3d-Symmetrie betragen d(PP) = 2,211 und d(PS) = 2,018 A. K2Mn[P2S6] ist isotyp zu K2Fe[P2S6] und der zweite Vertreter dieses Strukturtyps. Die beobachteten Fundamentalschwingungen von K2Mn[P2S6] stehen im Einklang mit der Faktorgruppenanalyse und werden auf der Basis von [P2S6]4−-Einheiten unter Berucksichtigung der Abweichung von der D3d-Symmetrie zugeordnet.

K2Fe[P2S6] was synthesized from the elements at 1173 K in sealed quartz tubes. The compound forms transparent orange crystals, stable against air and moisture. K2Fe[P2S6] crystallizes in the monoclinic system, space group P21/n (No. 14), with cell dimensions (T = 298.5 K) a = 6.0622(4), b = 12.172(1) and c = 7.3787(8) A, β = 101.113(7)°, Z = 2. The novel structure type (mP22) is characterized by columns of alternating face-sharing S6 octahedra and trigonal antiprisms (both distorted) parallel to the a axis, which are interconnected by inserted K+ (CN 10; {2,6,2}-polyhedra; d(KS) = 3.231 − 3.845 A). The S6 polyhedra of the columns are centered alternately by Fe (d(FeS) = 2.577 A) and P2 pairs which are inclined to the a axis by 73.4°. The bond lengths in the hexathiodiphosphate(IV) anions, [P2S6]4−, with approximate 3 2/m – D3d symmetry, are d(PP) = 2.20 and d(PS) = 2.02 A. The compound is paramagnetic above TN = 28 K with μ = 4.69 B.M. and orders antiferromagnetically below TN. The internal modes of the observed Raman and FIR spectra of K2Fe[P2S6] are in accord with the factor group analysis, and the spectra are assigned on the basis of [P2S6]4− units, taking into account the deviation from D3d symmetry. Synthese, Kristallstruktur, Magnetismus und Schwingungsspektrum von Dikaliumeisen(II)hexathiodiphosphat(IV), K2Fe[P2S6] K2Fe[P2S6] wurde aus den Elementen bei 1173 K in evakuierten, abgeschmolzenen Quarzampullen dargestellt. Die Verbindung bildet transparente, orangefarbene, luft- und feuchtigkeitsbestandige Kristalle. K2Fe[P2S6] kristallisiert monoklin, Raumgruppe P21/n (Nr. 14), mit den Gitterkonstanten (T = 298,5 K): a = 6,0622(4), b = 12,172(1) und c = 7,3787(8) A, β = 101,113(7)°, Z = 2. Der neuartige Strukturtyp (mP22) wird durch Saulen von alternierend flachenverknupften S6-Oktaedern und trigonalen Antiprismen (beide verzerrt) charakterisiert, die parallel zur a-Achse verlaufen und durch K+-Kationen (KZ 10; {2,6,2}-Polyeder; d(KS) = 3,231 − 3,845 A) miteinander verbunden sind. Die S6-Polyeder der Saulen werden alternierend durch Fe (d(FeS) = 2,577 A) bzw. P2-Paare zentriert, die zur a-Achse um 73,4° geneigt sind. Die Bindungslangen in den Hexathiodiphosphat(IV)-Anionen [P2S6]4− mit angenaherter 32/m—D3d-Symmetrie betragen d(PP) = 2,20 und d(PS) = 2,02 A. Die Titelverbindung ist oberhalb TN = 28 K paramagnetisch mit μ = 4,69 B.M. und ordnet unterhalb TN antiferromagnetisch. Die beobachteten inneren Moden der Raman- und Infrarotspektren von K2Fe[P2S6] stehen im Einklang mit der Faktorgruppenanalyse. Die Schwingungsbanden werden auf der Basis von [P2S6]4−-Einheiten unter Berucksichtigung der Abweichungen von der D3d-Symmetrie zugeordnet.

Water-free samples with the stoichiometries Na 3 PO 3 S, Na 3 PO 2 S 2 and Na 3 POS 3 have been prepared, and from vibrational spectra the ions PO 3 S 3− and PO 2 S 3− 2 have been found. POS 3− 3 seems to be unstable towards disproportionati under these conditions. Some distinct differences are seen between the vibrational spectra of water-free and water-containing samples. Ab initio calculations (SCF/triple split valence basis, MP2 energy) have been used to study the relative stability, geometry and vibrational spectra of the oxothiophosphate anions PO 3 S 3− , PO 2 S 3− 2 and POS 3− 3 . The significant deviations between calculated and experimental geometry, especially for PO 3 S 3− , are found to be due to the neglect of the counterions. The effect of several counterions is investigated, and based on these results a corrected resonance hydridization scheme for PO 3 S 3− is presented. By scaling the force constants in accordance with the observed inaccuracies in the calculated geometry a good fit to experimental frequencies is obtained, and the potential energy distribution (PED) is calculated. The scaling for PO 3 S 3− is supported by calculation of the influence of one Na + cation on the vibrational spectra.

Geometry, vibrational frequencies and IR intensities are calculated for α-P 4 S 4 by scaled quantum mechanical calculations at the 6-31G*/SCF and STO-3G*/SCF levels. For both basis sets the frequencies are scaled with factors close to or equal to those found for P 4 S 3 , and based on these results a revised assignment is proposed. The α-P 4 S 4 force field is transferred to the isostructural As 4 S 4 and As 4 Se 4 molecules and rescaled, and based on a good fit to experimental frequencies a new assignment is also proposed for these compounds.

A series of basis sets are evaluated for AlCl 3 and AlCl − 4 , and a common scaling factor derived for these compounds was transferred to Al 2 Cl 6 . 6-31G* calculations, scaled with a common factor of 0.92, give a good fit to all vibrational frequencies for AlCl 3 , AlCl − 4 and Al 2 Cl 6 , and there is also a qualitative fit between calculated and observed IR intensities. Extending the basis set does not lead to significant improvements, either for the geometry or for the vibrational frequencies. The calculations verify earlier assignments based on general valence force fields and predict frequencies for some unobserved bands. The SQM force fields for aluminium chlorides show large similarities with the isoelectronic thiophosphates; the main deviations can be attributed to more ionic bonds in the aluminium chlorides. A significant influence on the out-of-plane vibration in AlCl 3 by the basis set on the d -orbitals may indicate that π dp bonding plays a role. A remarkable and unexpected basis set sensitivity is found for the ν 6 ( B 1 g ) ring vibration in Al 2 Cl 6 .

2,4-Bis(methylthio)-2,4-dithioxo-1,3,2,4-dithiadiphosphetane, (CH3S)2P2S4 (called Davy reagent methyl) has been characterized by X-ray crystallography. The central part of the molecule is a P2S6 unit similar to that of the metathiodiphosphate anion P2S62−. The methyl groups are arranged in a “trans-closed” configuration that is quite remarkable. By energy calculations at the 6-31G*/MP2 level it is shown that the observed conformation has the lowest energy, but the discrimination is small and is counteracted by entropy effects. The Raman and IR spectra have been recorded, and the vibrational frequencies assigned to the “trans-closed” form of the molecule present in the crystal structure. Some additional bands have to be attributed to conformers. In the Raman spectrum of the title compound dissolved in trichlorbenzene, the “trans-out” conformer dominates, hence packing effects influence the conformation.

The compound CuHgPS4 crystallizes in the orthorhombic system, space group Pna21 (No. 33), Z = 4, with lattice parameters a = 12.660(3), b = 7.3498(7), c = 6.0943(4) A, and δcalc = 4.96 g/cm3. The title compound is stable in air and moisture and behaves as a semiconductor. The crystal structure consists of discrete tetrahedral PS43- anions joined together by Cu+ and Hg2+ cations. The arrangement of the sulfur atoms is approximately hexagonal close-packed in which P, Cu, and Hg occupy tetrahedral sites. The PS4, HgS4, and CuS4 tetrahedra are slightly distorted with mean distances d(P-S) = 2.055, d(Hg-S) = 2.524, and d(CuS) = 2.320 A, and 8% of the Hg atoms were found to be disordered, occupying interstitial tetrahedral sites. The title compound is isotypic to AgZnPS4 and can be considered to be a defect structure of Enargite (Cu3AsS4), which is a substitution derivative of the Wurtzite (ZnS) structure. The CuHgPS4 vibrational spectrum has been recorded. The internal modes experimentally observed are in accord with the factor group prediction. A tentative assignment of the vibrational frequencies is proposed.

Geometry, vibrational frequencies, IR intensities and potential energy distribution are calculated for P4S3 at the SCF/6–31G* level. With one scaling factor all observed frequencies are modelled with an accuracy of ± 1%, and a revised assignment is proposed. Transfer of the P4S3 force field to P4S3, As4Se3, As4S3, and PAs3S3 and rescaling yields a good fit for all these compounds. Where more than one scaling factor is needed, the different scaling factors are explainable. Revised assignments and potential energy distribution data are given for all these compounds. STO-3G* calculations give a poorer fit for P4S3, but with separate scaling of stretching and bending force constants a good fit is obtained.

Based on studies of PS 3 - and PS 4 3- , scaled quantum mechanical vibrational analyses are performed for P 2 S 6 2- (6-31G * level) and P 2 S 7 4- (STO-5G * level). The higher the overall charge density, the higher the required scaling factor, and the larger the inaccuracies of the calculated geometry and vibrational frequencies. Both effects are probably due to neglect of the counterions in the calculations. υ6 in P 2 S 6 2- is conclusively assigned, and its frequency is very sensitive to the basis sets for the d-orbitals and to the counterions

Water-free samples with the stoichiometries Na 3 PO 3 S, Na 3 PO 2 S 2 and Na 3 POS 3 have been prepared, and from vibrational spectra the ions PO 3 S 3− and PO 2 S 3− 2 have been found. POS 3− 3 seems to be unstable towards disproportionati under these conditions. Some distinct differences are seen between the vibrational spectra of water-free and water-containing samples. Ab initio calculations (SCF/triple split valence basis, MP2 energy) have been used to study the relative stability, geometry and vibrational spectra of the oxothiophosphate anions PO 3 S 3− , PO 2 S 3− 2 and POS 3− 3 . The significant deviations between calculated and experimental geometry, especially for PO 3 S 3− , are found to be due to the neglect of the counterions. The effect of several counterions is investigated, and based on these results a corrected resonance hydridization scheme for PO 3 S 3− is presented. By scaling the force constants in accordance with the observed inaccuracies in the calculated geometry a good fit to experimental frequencies is obtained, and the potential energy distribution (PED) is calculated. The scaling for PO 3 S 3− is supported by calculation of the influence of one Na + cation on the vibrational spectra.

Several SCF basis sets up to a McLean-Chandler “triple split” basis set with diffuse orbitals and polarization functions were employed to calculate energy, geometry and vibrational frequencies for PS 3 − and PS 4 3− . The best calculated frequencies were within 10% of the experimental values, and a reassignment of the observed frequencies for PS 3 − was performed on the basis of these calculations. Polarization functions are imperative to give an acceptable geometry, but minimal basis sets (STO-5G) yield surprisingly good predictions of vibrational frequencies. STO-5G * generally gives ca. 0.05 A shorter bond lengths than the split valence basis sets and gives too high stretching, but acceptable bending frequencies. There are almost no differences in the geometry and moderate differences in the vibrational frequencies obtained by the different split valence basis sets.

By ab initio quantum mechanical calculations on P2S2- 6 its equilibrium energy, geometry and vibrational frequencies along with their PED values have been obtained. The basis sets STO-5G, 6-31G, STO-5G* and 6-31G* were employed, and force field calculations were carried out at the STO-5G and the STO-5G* levels. The calculations show that the assignment for some bands between 180 and 260 cm -1 should be corrected. Two scaling factors were needed to fit the calculated frequencies with the observed frequencies within a deviation of less then 20 cm -1 for all vibrations, with the exception of v6(B1g). The calculated frequency of this vibration is very dependent on the polarization functions, and use of STO-2G for the 3d-orbitals corrects most of the deviation. STO-5G* and 6-31G* both give a good description of the geometry of the title ion, although STO-5G* yields a 0.04 Å too short terminal P - S distance.

Vibration spectra of solid and molten antimony trichloride were recorded. In the solid state, vibration frequencies in addition to those of the SbCl3 molecules with their C3, symmetry indicate bond fluctuations according to 2 SbCl3 ⇄Sb++ SbCl6 -.

Na4P2S7, Na2FeP2S7, and Ag4P2S7 were prepared by elemental synthesis at high temperatures and were characterized by vibration spectra and differential thermal analysis (DTA). A normal coordinate analysis was performed for P2S4−7. Additional vibration frequencies indicate the presence of the decathiotriphosphate anion P3S5−10. The formation of higher thiophosphates of the type PnS(n+2)-3n+1 with n ≥ 4 cannot be excluded.

Single crystals of rubidium hexathiodiphosphate(V), Rb 2 P 2 S 6 , have been obtained and investigated by single crystal X-ray diffraction, and IR/FIR and Raman spectroscopy. The title compound crystallizes isotypically to the potassium, caesium and thallium analogues in the orthorhombic space group Immm (no. 71) with a = 8.485(3), b = 6.953(3), c = 9.259(3) A, and Z = 2, final R1 = 0.0579 and wR2 = 0.0987. The crystal structure is characterized by discrete [P 2 S 6 ] 2- anions (edge-sharing double-tetrahedra) with D 2h symmetry. Rubidium is coordinated by ten sulfur atoms forming a slightly distorted two-capped tetragonal prism with a coordination number CN Rb 10. The FT-Raman and FT-IR/FIR spectra have been recorded and a factor group analysis was carried out.

The novel thiodiphosphate, [Na(12-crown-4)2]2[P2S6] · CH3CN, bis[di(12-crown-4)sodium] hexathiodiphosphate(V) acetonitrile solvate (1) has been synthesized by the reaction of Na2[P2S6] with 12-crown-4 in dry acetonitrile. The title compound crystallizes in the tetragonal space group P42/mbc (no. 135), with a = 15.184(1) A, c = 21.406(2) A and Z = 4 and final R1 = 0.0671 and wR2 = 0.0809. The crystal structure is characterized by discrete sodium-bound crown-ether sandwich cations, [Na(12-crown-4)2]+ and [P2S6]2− ions with D2h symmetry. Sodium ion is coordinated by the eight oxygen atoms of two crown-ether molecules to form a square antiprisma. Solvent molecules of CH3CN are statistically disordered. Distances and angles of the [P2S6]2− unit are similar to those in [K(18-crown-6)]2 [P2S6] · 2 CH3CN, and in K2[P2S6] and Cs2[P2S6]. The FT-Raman and FT-IR spectrum of the title compound has been recorded and interpreted, especially with respect to the P2S6 group and in comparison to the few known metal hexathiodiphosphates(V).

SbPO4 was synthesized via a new route by reacting antimony metal with meta-phosphoric acid, (HPO3)n at high temperatures. The Raman and IR spectra of the title compound were recorded and the vibrational modes assigned on the basis of a factor group analysis. The internal vibrations are derived from tetrahedral PO4 units (approaching Sb[PO4]) by the correlation method, although the structure is polymeric and not ionic.

1-Ethyl-3-methylimidazolium hexachloridophosphate, [EMIm][PCl6] (1), 1-ethyl-3-methylimidazolium hexachloridoniobate, [EMIm][NbCl6] (2), 1-butyl-4-methylpyridinium hexachloridophosphate, [1,4-BMPy][PCl6] (3), 1-butyl-4-methylpyridinium hexachloridoniobate, [1,4-BMPy][NbCl6] (4), and 1-butyl-3-methylpyridinium hexachloridoniobate, [1,3-BMPy] [NbCl6] (5) have been synthesized and characterized by single-crystal X-ray diffraction and Raman spectroscopy. All the saltlike compounds crystallize in the monoclinic space group: [EMIm][PCl6] (1): P21/c (no. 14), a = 7.698(1), b = 12.266(2), c = 15.019(2) A, β = 101.45(1)°, V = 1389.9(3) A3 and Z = 4; [EMIm][NbCl6] (2): P21/n (no. 14), a = 20.186(1), b = 7.084(1), c = 20.549(1) A, β = 98.46(1)°, V = 2906.6(4) A3 and Z = 8; [1,4-BMPy][PCl6] (3): P21/c (no. 14), a = 14.681(2), b = 7.242(1), c = 16.157(2) A, β = 101.55(1)°, V = 1683.0(3) A3 and Z = 4; [1,4-BMPy][NbCl6] (4): P21/c (no. 14), a = 15.163(2), b = 7.323(1), c = 16.205(2) A, β = 101.92(1)°, V = 1760.5(4) A3 and Z = 4; [1,3-BMPy][NbCl6] (5): P21/c (no. 14), a = 10.396(1), b = 23.050(2), c = 14.974(2) A, β = 102.28(1)°, V = 3505.9(6) A3 and Z = 8. Title compounds are built up by the mentioned bulky organic cations and octahedral [PCl6]−respective [NbCl6]− anions. No significant hydrogen bonding is observed between the organic cations and respective inorganic anions. FT-Raman spectra of the title compounds have been recorded and interpreted, especially with respect to the inorganic parts [PCl6]− and [NbCl6]−. NMR spectra and the melting temperatures of 1–5 are given.

Triclinic P1, a=6.276, b=7.262, c=10.200A, α=89.81, β=911.26, γ=93.52°, Z=1, R=0.071. The crystal structure of the Davy-reagent-methyl shows the molecule structure as a derivative of the hexathiometadiphosphate anion P 2 S 6 2- with covalent bonded methyl groups. The position of the ligands close to the P 2 S 2 -ring is not an effect of the size of the ligands. The much larger p-tolyl group is orientated in an equivalent way close to the P 2 S 2 -ring

The phase diagram of the system [Ph4P]Br/BiBr3 was investigated with the aid of DSC, TG and temperature dependent X-ray powder diffraction measurements. By varying the reaction conditions, stoichiometry and crystallisation conditions of the reaction between BiBr3 and [Ph4P]Br four polynuclear bromobismuthates are formed. We report here the crystal structure of the solvation product [Ph4P]3[Bi2Br9] · CH3COCH3, which crystallises with monoclinic symmetry in the S. G. P21/nNo. 14, a = 12.341(1), b = 32.005(3), c = 19.929(3) A, β = 99.75(2)°, V = 7758(7) A3, Z = 4 and the crystal structures of two modifications of the compound [Ph4P]4[Bi6Br22]. The α-form, crystallises with triclinic symmetry in the S. G. P1 No. 2, a = 13.507(4) A, b = 14.434(4) A, c = 17.709(5) A, α = 81.34(2)°, β = 72.42(2)°, γ = 72.53(2)°, V = 3132.7(1) A3, Z = 2. The high-temperature β-form, crystallises with triclinic symmetry in the S. G. P1 No. 2, a = 13.893(4) A, b = 14.267(3) A, c = 16.580(3), α = 100.13(2)°, β = 96.56(2)°, γ = 110.01(2)°, V = 2985.5(1) A3, Z = 2. Lattice parameters of [Ph4P]4[Bi8Br28] are also given. The thermal behaviour of the compounds and in addition the vibrational spectra of [Ph4P]3[Bi2Br9] · CH3COCH3 are presented and discussed. Das Phasendiagram des Systems [Ph4P]Br/BiBr3. Synthese, Kristallstruktur, thermisches Verhalten und Schwingungsspektren von [Ph4P]3[Bi2Br9] · CH3COCH3 und zwei Modifikationen von [Ph4P]4[Bi6Br22] Das Phasendiagram des Systems [Ph4P]Br/BiBr3 wurde mit Hilfe von DSC, TG und temperaturabhangiger Rontgendiffraktometrie untersucht. Durch Variation der Reaktionsbedingungen, der Zusammensetzung und der Kristallisationsbedingungen wurden vier unterschiedliche Bromobismuthate gebildet. Wir berichten uber die Kristallstruktur des Solvatationsproduktes [Ph4P]3[Bi2Br9] · CH3COCH3, das mit monokliner Symmetrie in der Raumgruppe P21/nNo. 14 und den Gitterparametern a = 12.341(1), b = 32.005(3), c = 19.929(3) A, β = 99.75(2)°, V = 7758(7) A3, Z = 4 kristallisiert und die Kristallstrukturen von zwei Modifikationen der Verbindung [Ph4P]4[Bi6Br22]. Die α-Form kristallisiert mit trikliner Symmetrie in der Raumgruppe P1, No. 2, mit den Gitterparametern a = 13.507(4) A, b = 14.434(4) A, c = 17.709(5) A, α = 81.34(2)°, β = 72.42(2)°, γ = 72.53(2)°, V = 3132.7(1) A3, Z = 2. Die Hochtemperaturmodifikation β kristallisiert ebenfalls triklin in der Raumgruppe P1, No. 2 mit den Gitterparametern a = 13.893(4) A, b = 14.267(3) A, c = 16.580(3), α = 100.13(2)°, β = 96.56(2)°, γ = 110.01(2)°, V = 2985.5(1) A3, Z = 2. Die Gitterkonstanten von [Ph4P]4[Bi8Br28] werden ebenfalls angegeben. Das thermische Verhalten der Verbindungen und die Schwingungsspektren von [Ph4P]3[Bi2Br9] · CH3COCH3 werden berichtet.