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The reaction of 4,4′‐bipyridylethane (bpe) and 4,4′‐dipyridyl disulfide (dpds) with Zn(OAc)2⋅2 H2O has led to the formation of two coordination polymers, [Zn(OAc)2(μ‐bpe)]⋅2 H2O (1) and [Zn(OAc)2(μ‐dpds)] (2). Both the compounds have zigzag coordination polymeric structures as revealed by X‐ray crystallography. However, the presence of two lattice water molecules in 1results in an interesting difference between the crystal structures. In 1, the carboxylate carbonyl oxygen atoms of the Zn(OAc)2groups from two different adjacent zigzag polymers and four lattice water molecules form 24‐membered hydrogen‐bonded rings (graph set notation, R66(24)). One of the two bpe ligands associated with each ZnIIcenter passes through the center of this ring to form a two‐dimensional hydrogen‐bonded coordination polymeric structure. In the solid state, the adjacent 24‐membered hydrogen‐bonded rings further fuse together through OH⋅⋅⋅O hydrogen bonds among four waters to form cyclic (H2O)4. This results in a one‐dimensional hydrogen‐bonded ribbon‐like polymer comprising fused alternating 24‐ and eight‐membered OH⋅⋅⋅O hydrogen‐bonded rings. One of the bpe ligands passes through the center of the larger ring to produce an unexpected single self‐penetrating three‐dimensional hydrogen‐bonded network with polyrotaxane‐like association. A neutron diffraction study provides a detailed description of the hydrogen bonds involved.

A series of trialkylammonium salts of indium and gallium thiocarboxylates, [Et₃NH][M(SC{O}Ph)₄]·H₂O (M = In3+ (1), Ga3+ (2)) and [n-Bu₃NH][In(SC{O}Ph)₄] (3), [R₃NH][In(SC{O}Me)₄] (R = Et (4) and n-Bu (5)) have been synthesized and characterized. The structure of 2 has been determined by single crystal X-ray diffraction and was found to be isomorphous and isostructural with [Et₃NH][In(SC{O}Ph)₄]·H₂O (1) reported earlier. Thermal properties of 1–5 were studied. Compound 4 exhibits a phase transition which was characterized by DSC. Thermogravimetric and pyrolysis experiments of 1, 3, 4 and 5 showed the formation of tetragonal β-In₂S₃ while 2 yielded poorly crystalline monoclinic Ga₂S₃. Thin films of tetragonal In₂S₃ were obtained on a Ni coated Si substrate by MOCVD experiments using 1. Under similar conditions, 2 resulted in a film containing both cubic γ-Ga₂S₃ and hexagonal Ni_0.96S. When a Cu coated Si substrate was used 1 deposited thin films of tetragonal CuInS₂, while 2 furnished a mixture of tetragonal Cu_1.96S and tetragonal CuGaS₂ films. The composition of the thin films also depends on the temperature employed during the growth process. The composition, stoichiometry, phase analysis and surface morphology of the thin films obtained have been unequivocally characterized using XRD, SEM, TEM, RBS, Selective Area Electron Diffraction and XPS. It appears that the decomposed product(s) of 1 and 2 react with the substrate to form the metal sulfide thin films.

A series of trialkylammonium salts of indium and gallium thiocarboxylates, Et3NHMSCOPh4·H2O M In31, Ga32 and n-Bu3NHInSCOPh43, R3NHInSCOMe4 R Et 4 and n-Bu 5 have been synthesized and characterized. The structure of 2has been determined by single crystal X-ray diffraction and was found to be isomorphous and isostructural with Et3NHInSCOPh4·H2O 1 reported earlier. Thermal properties of 1–5were studied. Compound 4exhibits a phase transition which was characterized by DSC. Thermogravimetric and pyrolysis experiments of 1, 3, 4and 5showed the formation of tetragonal β-In2S3while 2yielded poorly crystalline monoclinic Ga2S3. Thin films of tetragonal In2S3were obtained on a Ni coated Si substrate by MOCVD experiments using 1. Under similar conditions, 2resulted in a film containing both cubic γ-Ga2S3and hexagonal Ni0.96S. When a Cu coated Si substrate was used 1deposited thin films of tetragonal CuInS2, while 2furnished a mixture of tetragonal Cu1.96S and tetragonal CuGaS2films. The composition of the thin films also depends on the temperature employed during the growth process. The composition, stoichiometry, phase analysis and surface morphology of the thin films obtained have been unequivocally characterized using XRD, SEM, TEM, RBS, Selective Area Electron Diffraction and XPS. It appears that the decomposed products of 1and 2react with the substrate to form the metal sulfide thin films.

The synthesis and structure of the hetero-bimetallic compound [(Ph 3 P) 2 Ag(μ-Cl)(μ-SC{O}Ph&z.sbnd;S)In(SC{O}Ph) 2 ] have been reported. The compound was synthesized by reacting [(Ph 3 P) 2 AgCl], InCl 3 ·4H 2 O and NaSC{O}Ph in the ratio 1:1:3 in a mixture of solvents. The structure of the compound has been determined by X-ray crystallography. The compound contains a nonplanar AgClSIn core.

The compounds [Cu₃(μ-dppm)₃(SC{O}Me)₂][PF₆] 1, [Cu₃(μ-dppm)₃(SC{O}Ph)₂][X] (X = ClO₄ 2 or PF₆ 2a) were synthesized by treating Na⁺R{O}CS⁻ (R = Me or Ph) with a mixture of [Cu(MeCN)₄]X (X = PF₆ or ClO₄) and bis(diphenylphosphino)methane (dppm) in stoichiometric ratios. The structures of 1 and 2 have been determined by single crystal X-ray crystallography. The trinuclear core is held intact by the three bridging dppm ligands and two capping thiocarboxylate anions. One of the thiocarboxylate anions triply bridges to the Cu₃(μ-dppm)₃ core through a μ₃-S and the other by a μ₃-S,O bonding mode. Compounds [Ag₃(μ-dppm)₃(SC{O}Me)₂][X] (X = NO₃ 3 or ClO₄ 3a) and [Ag₃(μ-dppm)₃(SC{O}Ph)₂][ClO₄] 4 were prepared by treating Na⁺R{O}CS⁻ (R = Me or Ph) with dppm and the corresponding silver salt. The structures of 3 and 4 were determined by X-ray crystallography. Both the thiocarboxylate anions bond in μ-S fashion, thereby stabilizing the trinuclear core. In all the four crystal structures C–H  · · ·  O hydrogen bonding is present between one of the methylene hydrogen atoms and the carbonyl oxygen of the thiocarboxylate ligand. ³¹P NMR studies in solution at low temperatures reveal that all the compounds retain their trinuclear core in solution, while intramolecular exchange involving dppm does not cease even at lower temperatures. Attempts to prepare monocapped trinuclear cations, [M₃(μ-dppm)₃(SC{O}R)]²⁺, and binuclear neutral compounds, [M₂(μ-dppm)₂(SC{O}R)₂], yielded only the corresponding bicapped trinuclear compounds.