Search

Temperature control requires a lot of control regulator. It has wide applications in cement, metallurgy and other industrial fields. The key equipment in metallurgy , cement, refractory materials production is Rotary kiln, of which temperature is one of the important parameters of process control .The kiln of calcination temperature in rotary kiln is an important factor affecting the quality and output of the kiln, and even cause the collapse of the kiln, affecting the normal operation of production. Based on the analysis for several important factors affecting the kiln temperature, the paper presents the application of fuzzy control in temperature control of rotary kiln. A fuzzy controller was established using the matlab fuzzy toolbox. A simulink rotary kiln fuzzy control system simulation was carried out on the kiln temperature control simulation. The simulation results show that the system response speed is faster and has better robustness compared with the traditional PID control system.

A new 3d–4f heterometallic coordination polymer [Gd(H2O)3(NO3−)(CuL)2] H2O (1) (H3L = glycylglycine, N-[1-(2-hydroxy, phenyl)-propylidene]) has been synthesized and characterized by IR, elemental analysis, TGA and X-ray single-crystal diffraction. In the coordination polymer, two metallo-ligand CuLs are connected with Gd3 + ion to form a 1-D chain via carboxylate and carbonyl oxygen. The neighboring Cu–Gd–Cu chains are further connected by hydrogen bonds to form a two-dimensional structure. Magnetic studies for 1 reveal that ferromagnetic interactions (JCuGd = 1.30 cm− 1) between Cu(II) and Gd(III) centers are operating within the CuII–GdIII–CuII systems.

In the cement production process, cement quality is the most important indicator. One way to measure the quality of the cement is the cement particle size. Only the cement particle size is symmetrical and the specific surface area could reach the national standard that this kind of cement is qualified products. In actual production, the specific surface area is tested in laboratory through experiment. This process takes a long time, and the instantaneous value of specific surface area can not be got. This paper, auxiliary variables coming from the practical production site are used to get an instantaneous value through fuzzy control algorithm and other rules. VC++ 6.0 is used to program this algorithm. After a long period of actual operation, this method is proved to be effective, the instantaneous specific surface area is got and the precision is acceptable. This could guide the operator to change parameters of the equipment timely. This could be widely used and is easy to spread.

One new compound, [Ag(p-bix)]3[Ag(Hbtc)2]·2H2O (H3btc=1,2,4-benzenetricarboxylate, p-bix=1,4-bis(imidazol-1-ylmethyl)-benzene), has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, PXRD, luminescent analysis, and single-crystal X-ray diffraction. X-ray structural analysis revealed that 0-D unit [Ag(Hbtc)2]3− and two kinds of 1-D linear chain [Ag(p-bix)]∞+, can be found within the crystal structure. The combination of 0-D [Ag(Hbtc)2]3− unit and 1-D undulated chain [Ag1(p1-bix)]∞+ through weak Ag–O bond gave rise to 2-D anionic supramolecular doublelayer. Then the grids of the 2-D layer are threaded by 1-D linear cationic chain [Ag2(p2-bix)]∞+ to generate entangled 3-D architecture with unusual poly(pseudo-rotaxane)-type arrangements. Luminescent properties of the title complex were also studied in this paper.

A series of isostructural two-dimensional lanthanide complexes with the formula [Ln(Haqtc)(H2O)4·xH2O]n (Ln = Nd, 1; Sm, 2; Eu, 3; Tb, 4; Dy, 5; Er, 6.) were synthesized by treating H4aqtc (H4aqtc = anthraquinone-1,4,5,8-tetracarboxylic acid) with lanthanide(III) salts under hydrothermal conditions. 3-D structures are formed by inter-layer hydrogen bonds. Magnetic susceptibility measurements of complexes 4 and 5 in temperature range 2–300 K were performed, which showed dominant weak ferromagnetic interactions in 4 and slow magnetization relaxation in 5.

The waste heat boiler is an important part of waste heat power station in cement plant. So it is highly important to control the drum level of waste heat boiler within the allowed range. A Double-Stage fuzzy controller which is used to control the drum level of the waste heat boiler is presented in this paper. This method adds a secondary fuzzy controller to adjust the weight of the first fuzzy controller’s factor on the basis of a general fuzzy controller. Simulation results show that the double-stage fuzzy control system has fast respond speed, high precision and strong anti-jamming capability.

Employing the flexible tetrapodal ligand 1,2,3,4-tetra-(4-pyridyl)-butane (TPB) along with fumaric acid (H2FMA) as the bridges, a metal-organic framework of [Zn(TPB)(FMA)·(2H2O)] (1) was obtained and characterized by elemental analysis, spectral method (IR), single crystal X-ray diffraction, thermal gravimetric analysis (TGA) and fluorescent property. This polymer exhibits a three dimensional (3D) dense network with an interesting (4,4)-connected PtS topology. It also displays good thermal stability and strong photoluminescence in the blue region band. Thus it may serve as a candidate of thermally stable blue-light-emitting photoluminescent material.

A new rigid multicarboxylates anthraquinone-1,4,5,8-tetracarboxylic acid (H4AQTC) was synthesized based on a modified synthetic procedure from 2,5-dimethylfuran and maleic anhydride. This rigid ligand can be widely utilized to construct rigid porous MOFs which may be candidates of porous materials. Two new rigid porous MOFs {[Cd(AQTC)0.5(H2O)3]·H2O}n (1) and {[Ni(AQTC)0.5(BPY)0.5(H2O)3]·2H2O}n (2) based on this rigid ligand are reported (BPY = 4,4'-bpy). The adsorption properties of complexes 1 and 2 are investigated, and the Langmuir surface areas are measured to be 43.25 m2/g and 389.14 m2/g.

Two coordination polymers [Zn2(H2L)2(bbi)(H2O)2·H2O]n 1 and [Ni4(L)2(bbi)2(H2O)4·H2O]n 2 {H4L = methylenediisophthalic acid, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)} have been prepared under hydrothermal conditions and structurally characterized by X-ray diffraction analyses. Mononuclear 1 is a 1D ladder chain and bbi adopts trans-configuration linking two metal centers. Plus the hydrogen binding interactions, it formed a 3D two-fold perpendicular interpenetrating (4, 5)-connected framework. Binuclear units of 2 are connected by L4− and cis-bbi to generate a 3D (4, 6)-connected framework, in which twisted bbi with binuclear units generate the rare triflexure helix. In solid state, complex 1 exhibits yellowgreen emissions at ambient temperature. Magnetic measurements show that there exist weak ferromagnetic interactions in 2.

Two complexes of [Ni(dmit) 2 ] − (dmit 2− = 2-thioxo-1,3-dithiole-4,5-dithiolate) with nonmagnetic Schiff base cations, 1-(4-bromobenzylideneamino)pyridinium (4-BrBz-1-APy + ; 1 ) and 1-(3-nitrobenzylideneamino)pyridinium (3-NO 2 Bz-1-APy + ; 2 ), have been characterized structurally. Their striking structural feature is the deviation of the [Ni(dmit) 2 ] − anion from the square-planar environment around the Ni atom with 11.42° and 6.57° dihedral angles (between the mean molecular planes of two dmit 2− ligands) in 1 and 2 , respectively. These twists arise from the molecular packing interactions between the superimposed anion and cation. In 1 , the magnetic [Ni(dmit) 2 ] − anions are arranged into a wave-shaped regular spin chain, whose magnetism was well fitted by one-dimensional (1D) Heisenberg uniform linear antiferromagnetic chain with | J / k B | = 66 K. In 2 , 1D ladder-shape [Ni(dmit) 2 ] − chains are formed through lateral-to-lateral S ⋯ ⋯ S contacts between the adjacent anions, which are further aligned into a two-dimensional (2D) anion layer via van der Waals forces. Complex 2 shows Curie–Weiss-type paramagnetic behavior with Curie constant C = 0.421 emu K mol −1 and Weiss constant θ = −1.279 K. The broken-symmetry DFT approach was utilized to evaluate the magnetic coupling nature for 1 and 2 , the theoretical analyses performed at ubpw91/lanl2dz level and concerned the so-called “weak bonding” regime approaches qualitatively explained the magnetic behaviors of 1 and 2 .

Employing the multidentate ligand pyridine-2,3,5-tricarboxylic acid (H 3 PTC) as a bridge, a novel cadmium(II) coordination polymer [Cd 3 (PTC) 2 (bpy)(H 2 O) 4 ] ( 1 ) was obtained and characterized by single crystal X-ray diffraction. The PTC 3- ligand exhibits an interesting coordination mode to form a dense three-dimensional (3-D) framework of 1 . The complex displays good thermal stability and strong photoluminescence in the blue region band. Thus it may serve as a potential candidate of thermally stable blue-light-emitting luminescent material.

[Ni(hmp)(MeOH)Br]4 ⋅ 2H2O has been prepared by the reaction of 2-hydroxymethylpyridine with NiBr2 ⋅ 3H2O and characterized by IR, elemental analysis, powder X-ray diffraction, thermogravimetric analyses, magnetic measurements, and single crystal X-ray diffraction. The crystal structure shows two independent [Ni(hmp)(MeOH)Br]4 molecules in the asymmetric unit and [Ni4O4]4+ cubane-type cores. Each octahedral Ni(II) is bridged by four μ3-CH2O − fragments from four hmp − ligands. Magnetic studies show that ferromagnetic coupling gives an S = 4 ground state with significant magnetoanisotropy, and the parameters are J 1 = 8.56, J 2 = 2.28, D = −0.65 cm−1, and g ≈ 2.13.

Three new heterobimetallic acetylene complexes CpNiCo (CO)3 (PPh3) (PhC2C4H4-R-p) [R = H (2), Br (3), COCH2 (4)] have been synthesized in suitable yield (31–47%) via the reaction of (PhC2C3H4-R-p)CO2(CO)5 PPh2 with nickelcene in n-octane. The complex CpNiCo(CO)3 (Ph2C3) (1) has also been obtained in 12% by the reaction of (Ph2C2) Co2 (CO)4 with nickelcene. The complexes have been characterized by elemental analysis, IR and 1H NMR. Electrochemical study of redox couples of these complexes was presented by using cyclic voltammetry on Pt electrodes in acetone. At room temperature, all complexes underwent electrochemically reversible or guasi-reversible oneelectron oxidation or reduction to the stable radicals. The radical anions of the complexes could be easily detected by ESR method in situ electrolysis in the THF solution. The isotropic parameters, CO=2.20mT, = 2.052 for the radical anion of complex 1, CO= 2.20 mT, P = 1.42 mT, =2.057 for the radical anion of complex 2, might indicate that NiCoC2 framework is a delocalized unit and the ligand obitals in the complex have more contribution to the LUMO of the complex.

Cyclic voltammetric studies of clusters (C5H5-C2C6 H4-R-p)Co2(CO)6-n Ln[n=0,2; L=PPh3, P(OEt)3] and (RCH2C)2Co2(CO4) (PPh3)2 on Pt electrode are described. The primary reduction (0 / −1) and oxidation (+ 1 / 0) steps are considered as a mono-electron process for all clusters. For the clusters (C5H5C2C6H4-R-p)Co2(CO)6, a good linear relation between reduction potential Epred and Hammett constant σp of R in the clusters is found. For the clusters (RC2R')Co2(CO)4L2, their radical anions are extremely unstable at room temperature and fragment into a series of mononuclear species, one of which is (RC2R')Co(CO)2PPh3. The reaction of radical anions of (RC2R')Co2(CO)6–n (PPh3)n(n=0,2) with PPh3 also produces mononuclear species (RC2R')Co(CO)2PPh3 which has been detected by means of cyclic voltammetry and ESR. The influence of R on redox properties of clusters is discussed.

Eight new complexes with the formula [PhC2C(OH)R1R2]Co2(CO)4 were prepared from phenyl substituted propargylic alcohols and dicobalt octacarbonyl. The reactions of these propargylic alcohol complexes with active methylene compounds, 2,4-pentanedione or ethyl acetoacetate, in the presence of an acid, HBF4(40%) + P2O5 (in excess) or BF2·Et2O, at room temperature in dichloromethane were investigated. From the 1-alkyl substituted tertiary propargylic alcohol complexes, three new conjugated ene-yne complexes produced by intramolecular dehydration reaction were isolated in high yields (82–95%). On the other hand, four new alkylated complexes were obtained with satisfactory yields (44–66%) from the secondary propargylic alcohol complexes. The influence of other acids, phosphorus pentoxide and polyphosphoric acid, on both dehydration reaction and alkylated reaction was also studied.

The supramolecular inclusion compound of β-cyclodextrin (β-CD, host) with (η5-cyclopentadienyl)tricarbonylmanganese [MnCp(CO)3, guest] was obtained in a crystalline state. The host-guest compound is thermally stable and do not liberate the guest on heating at 100°C in vacuum. It was characterized by elemental analysis, 1H NMR, differential scanning thermal (DSC) analysis and TLC. Continuous variation plot by NMR method shows that β-CD formed 1:1 inclusion compound with MnCp(CO)3. On the basis of 1H NMR spectra and the model building with Corey Pauling Koltum (CPK) models, the most probable inclusion mode is proposed.

Reaction of NdCl3, with AlCl3 and mesitylene in benzene gives complex [Nd(eta (6)-1,3,5-C6H3Me3) (AlCl4)(3)] (C6H6) (1) which was characterized by elemental analysis, IR spectra, MS and X-lay diffractions. The X-ray determination indicates that 1 has a distorted pentagonal bipyramidal geometry and crystallizes in the monoclinic, space group P2(1)/n with a = 0.9586(2), b = 1.1717(5), c = 2.8966(7) nm, beta = 90.85 (2)degrees, V = 3.2529(6) nm(3), D-c = 1.573 g/cm(3), Z = 4. A comparison of bond parameters for all the reported Ln(eta (6)-Ar) (AlCl4)(3) complexes indicates that the bond distance of Ln-C is shortened with the increasing of methyl group on benzene and with the decreasing of radius of lanthanide ions.

1D spin-Peierls-like complexes assembled from [Ni(mnt)2]− with Λ-shaped 1-(4′-R-benzyl)pyridinium derivatives (R represents a substituent) are reviewed, with data on their crystal structures, magnetic properties under ambient conditions as well as under pressure, and the nature of the paramagnetic-to-nonmagnetic transition. In this series of 1D spin systems, the correlation between the magnetic exchange and the anion stacking pattern is addressed by application of density functional theory (DFT) combined with a broken-symmetry approach. The qualitative relationship between the transition enthalpy change and the variation of the magnetic susceptibility in the low-temperature phase is determined. The influence of nonmagnetic doping on the structural and magnetic properties and the magnetic transitions are reported. Furthermore, the effect of the substituent group in the phenyl ring of the cation on the transition temperature and the origin of the transition are discussed.

Employing nicotinamide and 2-nitrobenzoate as mixed ligands, a new complex was obtained and characterized by single crystal X-ray diffraction, [Co(C7H5NO4)2(C6H5NO2)2(H2O)2]·2H2O ( 1 ). It is connected by the strong O–H…O and N–H…O hydrogen bonds to form a two-dimensional (2-D) supramolecular network. The biological activity of complex 1 was investigated and the results indicate that it is an effective inhibitor of vascular endothelial growth factor receptor-2 tyrosine kinase (VEGFR-2 TK) with an IC50 value of 608 nM.

Three new interesting coordination polymers, [Zn(PDCO)(H2O)·H2O]n (1), [Co(PDCO)(H2O)3]n (2) and [Mn(PDCO)(H2O)2]n (3), (H2PDCO = pyridine-2,4-dicarboxylic acid N-oxide), have been prepared under hydrothermal conditions and structurally characterized. Polymer 1 exhibits 0D Zn units, polymer 2 features 1D infinite zigzag Co chains. In polymer 3, four Mn atoms and four PDCO ligands form a 24-member ring and these rings are interlocked to form a 2D infinite layer. Compounds 1–3, with systematic variation in dimensionality from 0D to 1D to 2D, are the first examples of metal coordination polymers into which pyridine-2,4-dicarboxylic acid N-oxide has been introduced. In addition, the photoluminescent properties of 1 as well as the magnetic behavior of 2 have been investigated.

Three complexes of [Ni(mnt)2]− (mnt2− = maleonitriledithiolate) with benzylpyridinium derivatives, 1-(2′,6′-dichlorobenzyl)-4-aminopyridinium (abbr. Cl2BzNH2Py+) and 1-(2′,6′-dichlorobenzyl)quinolinium (abbr. Cl2BzQl+), have been characterized structurally and magnetically. The [Cl2BzNH2Py][Ni(mnt)2] solution in MeCN was slowly evaporated to give the crystals of 2, whilst its solution in i-PrOH/MeCN yields 2·0.5i-PrOH. The [Ni(mnt)2]− anions are arranged in the mixed stacks of anions and cations in 2, and the segregated stacks of anions and cations in 2·0.5i-PrOH and 4. Even though three complexes exhibit different stacking pattern of magnetic anions, their temperature dependences of magnetic susceptibilities in 2–300 K range show a common feature, namely, two broad maxima of magnetic susceptibility. Powder X-ray examination for three complexes excluded that the impurity causes such complicated magnetic behaviors. Combined with the single crystal structure analyses, the double broad maxima of magnetic susceptibility is probably attributed to anisotropic magnetic exchange interactions between magnetic anions.

Two new molecular solids, [1-NaMePid][Ni(mnt)2] (1) and [2-NaMePid][Ni(mnt)2] (2) (mnt2− = maleonitriledithiolate, [1-NaMePid]+ = 1-(1′-naphthylmethyl)piperidinium and [2-NaMePid]+ = 1-(2′-naphthylmethyl)piperidinium) have been characterized structurally and magnetically. Both [Ni(mnt)2]− anions and the cations of 1 and 2 form segregated column stacks, and the Ni(III) ions form a 1D zigzig alternating magnetic chain within a [Ni(mnt)2]− column through Ni···S, S···S, Ni···Ni, or π···π interactions. Some conformational features in two isomeric cations and the geometry of the individual [Ni(mnt)2]− anion for 1 and 2 remain similar, while the changes of the space filling properties, the packing requirements and the existence of the water molecule in 2 result in the difference of the stacking mode of the [Ni(mnt)2]− anions. Magnetic susceptibility measurements in the temperature range 2–300 K show that 1 is diamagnetism, while 2 exhibits a novel and interesting spin–gap transition around 16.8 K with antiferromagnetic interaction (J = −4.6 cm−1) in the high-temperature phase (HT) and the spin–gap (Δ/kb = 68.5 K) in the low-temperature phase (LT).

A novel bilayered coordination polymer with nanoporous channels [Ni3(bix)3(PTCO)2 (H2O)4·6H2O]n (1) has been synthesized and the permanent porosity of (1) is confirmed by N2 adsorption isotherm measurement.

Three novel 3D metal–organic frameworks, [Co2(butca)(o-bix)2·8H2O]n (1), [Co2(butca)(m-bix)2·2H2O]n (2) and [Co2(butca)(p-bix)2·3H2O]n (3) (butca = 1,2,3,4-butane-tetracarboxylic acid; o-bix = 1,2-bis(imidazol-1-ylmethyl)-benzene; m-bix = 1,3-bis(imidazol-1-ylmethyl)-benzene; and p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene), have been successfully synthesized from a 2D layer compound [Co2(butca)(H2O)5·2H2O]n (0) employing a three isomer pillars insertion reaction, and their structures were determined by single-crystal X-ray diffraction studies. Complexes 1 and 2 are isostructural. Interestingly, there exist metal-bix double-helical chains in these two 3D frameworks, which are arranged left- and right-handed alternately. Different from 1 and 2 which have only one coordination model, Co atoms in 3 have two types of different coordination enviroments. The Co1 ions are exclusively bridged by cis-bix ligands to give one 26-number ring through spontaneous resolution. At the same time, the Co2 ions are wholely connected with tran-bix ligands to form a 1-D zigzag chain. Moreover, the relationship between a 2D layer structure and 3D metal–organic frameworks based on the pillared-layer motifs is discussed. This work has significant potential for the study of crystal engineering of transition metal coordination networks.

Syntheses, structural characterizations, magnetic behaviors and theoretical analyses of two new ion-pair complexes, [IFBzIQl][Ni(mnt)2](1) and [IClBzIQl]2[Ni(mnt)2]2 · MeCN(2) [IFBzIQl][Ni(mnt)2] ([IFBzIQl]+ = 1-(2′-fluoro-4′-iodobenzyl)isoquinolinium, [IClBzIQl]+ = 1-(2′-chloro-4′-iodobenzyl)isoquinolinium, mnt2− = maleonitriledithiolate), have been investigated. In crystal of 1, the [Ni(mnt)2]− anions and the [IFBzIQl]+ cations stack into an alternating column through π⋯π stacking interactions. The anions of both 1 and 2 form a dimer via π⋯π stacking and S⋯S short interactions between the [Ni(mnt)2]− anions. The overlapping mode of two neighboring [Ni(mnt)2]− anions in the dimer is the Ni-ring fashion with a Ni⋯Ni distance of 4.076 A for 1, and ring–ring fashion with the Ni⋯Ni and S⋯S distances being 4.395 and 3.593 A for 2. Some weak interactions such as π⋯π, C⋯N, C–H⋯F or C–H⋯N in 1 and 2 play a crucial role in stacking and stabilizing the crystal lattice, and give a 3D network structure and exchange pathways of the magnetic interaction for 1 and 2. Magnetic susceptibility measurements for 1 and 2 in the temperature range 1.8–300 K show that the overall magnetic behavior indicates the presence of antiferromagnetic interaction, while 2 exhibits an activated magnetic behavior in the high-temperature region (HT) together with a Curie tail in the low-temperature region (LT).

Three isomeric nitronyl nitroxide radical compounds, 2-[n-(N-benzyl)pyridinium]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide bromide (n = 2, 3 and 4 for 1, 2 and 3, respectively), have been synthesized and structurally characterized. The influence of steric hindrance on the molecular packing structures and physical properties has been observed. In the radical 1, such steric hindrance leads to a folding conformation of the imidazoline and benzene rings and the intramolecular C–H…π interaction between the methyl group and the benzene ring. There is no such effect in 2 and 3. In crystal of 2, there are the intermolecular C–H…π between methyl groups and benzene ring and intermolecular π…π stacking interaction between pyridine and benzene rings. Crystal of 2 with a chiral space group P212121 shows the SHG response about 0.4 times as that of urea. In crystal of 3, there are three symmetry-independent radical molecules, which form an unusually six-membered supramolecular ring via intermolecular O…π interactions. For the solid sample of 3, the X-band EPR exhibits an axially symmetric signal and magnetic susceptibility data suggest intermolecular antiferromagnetic (AFM) coupling interactions and very weak intermolecular ferromagnetic (FM) coupling interactions which is more likely caused by magnetic anisotropy, while measurements of both 1 and 2 show isotropic X-band EPR signals and simple Currie–Weiss magnetic behavior.

Two new salts, [2-NaMePy]2[Ni(i-mnt)2] (1) and [2-NaMe-4-MePy]2[Ni(i-mnt)2] (2) ([2-NaMePy]+ = 1-(2′-naphthylmethyl)pyridinium, [2-NaMe-4-MePy]+ = 1-(2′-naphthylmethyl)-4-methylpyridinium and i-mnt2− = iso-maleonitriledithiolate), have been prepared and characterized by elemental analyses, UV, IR, molar conductivity, and single crystal X-ray diffraction. The anions in 1 form a 1-D chain through short C ··· N interactions between the anions, while the cations in 2 stack a 1-D column via C–H ··· π and π ··· π stacking interactions between the cations. The effect of weak intramolecular interactions such as C–H ··· N, C–H ··· S, C–H ··· Ni hydrogen bonds, and π ··· π stacking interactions between the cations and the anions further generate a 3-D network structure. The change of the molecular topology of the countercation when the 4-substituted group in the pyridine ring is changed from H atom to CH3 group results in different crystal system, space group, and the stacking mode of the cations and anions of 1 and 2.

A new ion-pair complex, [BzTPP]2[Ni(i-mnt)2](1) (i-mnt2− = iso-maleonitriledithiolate, [BzTPP]+ = benzyltriphenylphosphinium) was synthesized and characterized by elemental analysis, IR, UV, EI-MS spectra and single crystal X-ray diffraction. The single-crystal structural analysis shows that 1 crystallizes in the triclinic space group P-1, with a = 9.466(1) A, b = 10.196(1)A, c = 29.252(3)A, α = 99.28(1)∘, β = 93.96(1)∘, γ = 106.34(1)∘, V = 2654.3(4)A3, Z = 2. The Ni(II) ions of the [Ni(i-mnt)2]2 − anion adopted a square-planar coordination geometry. Four weak C─H…N hydrogen bonds between the anions and the cations observed in the crystal give further rise to a 3D structure.

Two new molecular magnets, based on [Ni(mnt) 2 ] − monoanion, [DiBrBzPy][Ni(mnt) 2 ] ( 1 ) and [DiBrBzIQl][Ni(mnt) 2 ] ( 2 ) ([DiBrBzPy] + = 1-(3′,5′-dibromobenzyl)pyridinium, [DiBrBzIQl] + = 1-(3′,5′-dibromobenzyl)isoquinolinium and mnt 2− = maleonitriledithiolate), were prepared and characterized by elemental analyses, IR, ESI-MS spectra, single crystal X-ray diffraction and magnetic measurements. The [Ni(mnt) 2 ] anions and the cations of 1 and 2 are alternately stacked and form 1D column via π⋯π stacking interactions between the [Ni(mnt) 2 ] anions and the neighboring cations. Some weak Ni⋯N, C⋯N interactions and C H⋯Br, C H⋯N hydrogen bonds between the adjacent columns further generate a 3D network structure. Magnetic susceptibility measurements show that both 1 and 2 exhibit the typical magnetic behavior of a spin gap system with an energy gap of 1151.9 K for 1 and 73.9 K for 2 .

Two new molecular magnets, [RBzPyN(CH{sub 3}){sub 2}][Ni(mnt){sub 2}] [mnt{sup 2-}=maleonitriledithiolate; [RBzPyN(CH{sub 3}){sub 2}]{sup +}=1-(4'-R-benzyl)-4-dimethylaminopyridinium; R=CN(1), F(2)], with unusual magnetic properties have been prepared and characterized. Both 1 and 2 form a 3D network structure in which the [Ni(mnt){sub 2}]{sup -} anions form a 1D magnetic chain for 1 and a stepwise stack for 2via weak {pi}...{pi} stacking interactions, C...C or C...N short interactions between the neighboring anions. Magnetic susceptibility measurements in the temperature range 1.8-300 K indicated that 1 and 2 show unusual spin gap transition around 30 K and 110 K, respectively. The transition for 1 and 2 is the second-order phase transition as determined by the capacity measurement. - Graphical Abstract: Two new molecular magnets based on [Ni(mnt){sub 2}]{sup -} monoanion form a 1D magnetic chain for 1 and a stepwise stack for 2, and exhibit unusual spin gap transition.

Three new ion-pair complexes, consisting of 1-benzyl-4-aminopyridinium with [M(mnt) 2 ] 2− where mnt 2− = maleonitriledithiolate and M = Ni 2+ , Pd 2+ or Pt 2+ for complexes 1 – 3 , have been synthesized and structurally characterized. X-ray single crystal studies revealed that three complexes are isostructural and crystallize in monoclinic space group C 2 /c , and there exist weak H-bonding interactions between –NH 2 groups of cation and –CN group of anion as well as weak M…H-bonding interactions between anions and cations. The calculations of charge density distribution disclosed that the M…H-bonding interaction in crystals of 1 – 3 is mainly attributed to static electric interactions. Two types of H-bonding interactions lead to the formation of two-dimensional sheet structure which is parallel to the crystallographic bc -plane in the crystals of 1 – 3 . A near-IR absorbance appears in the UV–vis-NIR spectra of 1 and 3 , respectively, while does not come out in the spectra of 2 .

Four new molecular solids, [1-(2′-F-4′-R-benzyl)pyridinium][bis(maleonitrile dithiolato)nickel] (abbreviated as [RFBzPy][Ni(mnt) 2 ], R = F ( 1 ), Cl ( 2 ), I ( 3 ), H ( 4 )), have been prepared and characterized. The Ni(III) ions in 1 – 3 form a 1D zig-zag chain within a Ni(mnt) 2 − column. The chain is uniform in 2 and 3 , while it is alternating in 1 . The cations and Ni(mnt) 2 ions of 4 stack in complicated way in which the stacking of Ni(III) ions shows an ACA-type repeat unit. Magnetic susceptibility measurements in the temperature range 1.8–300 K show that 1 and 4 are diamagnetic, whereas 2 and 3 exhibit ferromagnetic coupling behavior. The χ M T of 2 and 3 can be well reproduced by the Baker equation for a 1D S = 1/2 magnetic chain with g = 2.01, J = 17.8 cm −1 for 2 , and g = 2.04, J = 41.1 cm −1 for 3 .

Six new inorganic–organic polymers {Mg(H2MDIP)(H2O)4]·3H2O}n (1), {Ca2(MDIP)(H2O)4]·CH3OH·4H2O}n (2), {[Sr2(MDIP)(H2O)7]·2H2O}n (3), {[Ba(MDIP)0.5(H2O)4]·H2O}n (4), {[Mn(H2MDIP)(H2O)]2·H2O}n (5) and {[Co(H2MDIP)(H2O)]2·H2O}n (6) were obtained by self-assembly of the corresponding metal salts with methylenediisophthalic acid (H4MDIP), and their structures were determined by single-crystal X-ray diffraction studies. Monodentate coordination mode of H2MDIP2− in 1 results in a 1D chiral chain (right-handness) with a monoclear magnesium center. Complexes 2–4 have 2D layer networks, and each MDIP4− ligand coordinates to Ca(II), Sr(II) or Ba(II) atoms using four carboxylate groups: the chelating-mono coordination mode in 2 leads to a 1D helical chain, yet the chelating-mono and chelating coordination modes lead to binuclear [Sr–O–Sr] and [Ba–O–Ba] units in 3–4. Both 5 and 6 have 2D grid structures with a binuclear [M–O–C–O–M] unit (M = Mn2+, Co2+). The luminescence properties of 1–4 have been investigated in the solid state at ambient temperature and it was found that the strong emissions vary from blue to yellow–green fluorescence depending on the metal ions. Compound 1 exhibits good second-harmonic generation activity, approximately 1.1 times that of urea.

A new inclusion complex of β-cyclodextrin with sodium maleonitriledithiolate (Na2mnt) was investigated by electronic spectra, induced circular dichroism (ICD), and quantum mechanics (QM) methods. The orientation of the guest anion inside the host cavity was studied by ICD spectra and analyzed by structural optimization using PM3 quantum chemical method. Finally, the inclusion constant was determined by both a linear and a non-linear fitting methods, which were based on the variation of ICD signals of the guest upon inclusion complexation with the host. The inclusion constant of Na2mnt/β-cyclodextrin was estimated to be (2.45 ± 0.15) × 103 or (3.10 ± 0.11) × 103 M−1 in solution by these two fitting methods.

The X-ray crystal structures of (NH4)2(15-crown-5)3[Cu(mnt)2] (1) and (NH4)2(benzo-15-crown-5)4-[Cu(mnt)2]·0.5H2O (2) were determined. Two single crystals are composed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2]2− anion. The triple-decker dication in complex 1 and a sandwich dimmer in complex 2 were observed. X-Band EPR studies on the single crystals of both complex 1 and complex 2 have been carried out at room temperature, which revealed that complex 2 showed a perfect hyperfine structure of Cu whereas that of complex 1 could not be observed. The principal values and direction cosines of the principal axes of the g and A tensors were computed by a least-squares fitting procedure. The spin density of Cu(II) was estimated according to the principal values of the A tensors and compared well with the results calculated based on DFT method.

A organic cation, [NO2BzIQl]+([NO2BzIQl]+ = 4-nitrobenzylisoquinolinium), that acts as a courterion in assembling Ni ( mnt ) 2 - (mnt2− = maleonitriledithiolate), results in the forming of a new molecular solid [NO2BzIQl][Ni(mnt)2] (1) in which the anions and cations stack into columns in the solid state and the Ni(III) ions form a 1D zigzag alternating chain through Ni⋯S and π⋯π interactions between anions with the Ni⋯Ni distances of 3.907 A and 3.977 A within a Ni(mnt)2 column. Magnetic susceptibility measurements show that 1 exhibits a spin gap transition with a second-order characteristic by DSC determination around 230 K.

Five new interesting transition metal coordination polymers [MnL2(bpy)2(H2O)2]n (1) (H2L = 4-carboxymethylbenzoic acid) (bpy = 4,4′-bipyidine), [CoL(bpy)(H2O)3 · H2O]n (2), [CdL(bpy)(H2O)3 · H2O]n (3), [Cu2L(bpy)2 · 3H2O]n (4) and [Zn2L2(bpy) · H2O]n (5) have been synthesized under solvothermal conditions and structurally characterized. This series of complexes has shown an intriguing variety of architectures, which firstly form zero- to two-dimensional frameworks by metal–ligand interactions, and secondly form three-dimensional supramolecular frameworks by intermolecular interactions such as hydrogen bonds. Compound 3 shows strong blue fluorescent emissions in the solid state upon photo-excitation at 359 nm at room temperature and may be an excellent candidate for blue-fluorescent materials. Compound 4 appears to be a good candidate for new hybrid inorganic–organic NLO materials.

Three silver complexes Ag 2 (L) 2 (NO 3 ) 2 ( 1 ), Ag 2 (L) 2 (SO 3 CF 3 ) 2 (H 2 O) 0.5 ( 2 ), and [Ag 2 (L) 2 (NO 3 ) 2 ] n ( 3 ) were prepared from molecular clips, 2,2′-Bis(imidazol-1-ylmethyl)-biphenyl ( L ) and structurally characterized to investigate the structural-luminescent relation. Compound 1 is a bimetallic supramolecular rectangle in which two L ligands are connected by two linearly coordinated Ag(I) ions. Compound 2 is described as a double helicate due to the nature of the twist of the imidazole groups after coordination to Ag(I) centers. In compound 3 , the Ag(I) centers are connected by L ligands into a one-dimensional zigzag chain. Solid state and solution fluorescent measurements exhibit the presence of ligand-based emission at 415 and 435 nm of compounds 1 and 2 , respectively. It is said that the dihedral angles between the two imidazole rings coordinated to one Ag(I) center affect the emission properties.

The hydrothermal assembly of CoCl2 · H2O with benzene-1, 2, 3, 4-tetracarboxylic acid (H4mpda) yielded a novel lamellar coordination polymeric complex, Co2mpda(H2O)6 · H2O (1), in which each layer presents an interesting multifold topology: both as partially overlapped helices with alternate chirality and as alternately arranged ladders and zigzag chains.

A new Late Jurassic docodontan shows specializations for a subterranean lifestyle. It is similar to extant subterranean golden moles in having reduced digit segments as compared to the ancestral phalangeal pattern of mammaliaforms and extant mammals. The reduction of digit segments can occur in mammals by fusion of the proximal and intermediate phalangeal precursors, a developmental process for which a gene and signaling network have been characterized in mouse and human. Docodontans show a positional shift of thoracolumbar ribs, a developmental variation that is controlled by Hox9 and Myf5 genes in extant mammals. We argue that these morphogenetic mechanisms of modern mammals were operating before the rise of modern mammals, driving the morphological disparity in the earliest mammaliaform diversification.

Two novel ion-pair complexes, [RBzIQl] + [Ni(mnt) 2 ] − (mnt 2− = maleonitriledithiolate, [RBzIQl] + = 4-R-benzylisoquinolinium; R = H ( 1 ), Cl ( 2 )) have been characterized structurally and magnetically. The Ni ( mnt ) 2 - anions and [BzIQl] + cations of 1 form 1D column of alternating between cations and anions via π⋯π stacking interaction between Ni(mnt) 2 plane and isoquinoline ring, and the Ni(mnt) 2 anions between adjacent columns exist C⋯N, C⋯N, and N⋯N interaction. The anions and cations of 2 stack into well-segregated columns in the solid state; and the Ni(III) ions form a 1D zigzag chain in a Ni(mnt) 2 column through intermolecular Ni⋯S, S⋯S, Ni⋯Ni or π⋯π interactions. The chain is uniform in 2 with the Ni⋯Ni distances of 3.784 A. Magnetic susceptibility measurements for these complexes in the temperature range 1.8–300 K show that 1 exhibits antiferromagnetic coupling behavior, and 2 exhibits unusual magnetic phase transitions around 45 K. The overall magnetic behavior for 2 indicates the presence of antiferromagnetic interaction in the high-temperature phase (HT) and spin gap in the low-temperature phase (LT).

A new molecular solid, [1-(4′-iodobenzyl)pyridinium]-bis(maleonitriledithiolato)nickel, [IBzPy][Ni(mnt)2] (1), has been prepared and characterized. The Ni ( mnt ) 2 − anions and [IBzPy]+ cations of 1 form completely segregated uniform stacking columns with the Ni⋯Ni distance 3.956 A in the column. The temperature dependence of the magnetic susceptibility reveals that 1 undergoes a magnetic transition around 120 K, and exhibits an antiferromagnetic interaction in the high-temperature phase and a spin gap in the low-temperature phase. The DSC analyses further reveals that the phase transition is first order.

Two new cobalt(II) coordination polymers, [Co(PDCO)(H2O)2]n (1) and [Co(PDCO)(bix)(2H2O)2·H2O]n (2) ( PDCO= pyridine-2,6-dicarboxylic acid N-oxide, bix = 1,4-bis(imidazol-1-ylmethyl)-benzene) have been synthesized under hydrothermal conditions. Single-crystal X-ray analyses show that compound 1 is a 1D helical chainlike structure with 41 screw axes parallel to the crystallographic c-axis and interchain hydrogen-bonding interactions further result in a 3D framework; for compound 2, each bix ligand connects two Co1 atoms (or two Co2 atoms) to give a zigzag chain structure and these 1D chains are connected by offset face-to-face π···π and hydrogen bond interactions to generate a 3D architecture. The thermogravimetric analyses were investigated for 1 and 2. The determination of variable temperature magnetic susceptibilities indicates an antiferromagnetic interaction between the metal atoms for 1 and 2.

A coordination polymer, [Cu2(2,2′,3,3′-odpa)(H2O)3] · (H2O) (2,2′,3,3′-odpa = 2,2′,3,3′-oxydiphthalic acid) (1), has been obtained. Single crystal X-ray diffraction analysis indicated that 1 has a 2D distorted brick wall structure (63-nets) constructed from tetracopper(II) SBUs. The relationship between its magnetic property and structure also has been investigated.