Solvothermal Syntheses, Crystal Structures And Properties Of Organic Hybrid Chalcogenidometalates

Organic hybrid chalcogenidometalate materials have attracted considerable interest, because they are a new type of materials with unique topologic structures and properties of catalysis, adsorption, ion-exchange, electronics, optics, nonlinear or semiconductor. The syntheses of these materials are typically carried out under hydro(solvo)thermal conditions at relatively low temperatures. Tetrahedral ortho-anions MQ4 (M = Ga, In, Sn, Sb; Q = S, Se, Te) or pyramid anions MQ3 (M = Sb; Q = S, Se) as primary building unit exhibit a characteristic tendency to condense through corner- or edge-bridging to afford a variety of structures of the chalcogenidometalate anions, whose counterions are the protonated non-chelating amine or tetra-alkylammonium. The goal of this work is to explore several synthetic systems containing main Group 13, 14 or 15 metal elements and chalcogen (S, Se and Te) under mild solvothermal conditions. Using chelating amine amines or metal complex cations as structure-directing agents or templates, a series of chalcogenidometalates including Ga, In, Sn and Sb were synthesized, and the effects of the chelating amines on the syntheses of chalcogenidometalates have been discussed. In addition, a series of organic hybrid coordination polymers containing dimethyl sulfide as bridging ligands were synthesized by replaced chalcogen with dimethyl sulfide under similar solvothermal condition. Their reaction conditions, thermal stabilities, optic, and semiconductor properties are discussed and studied in detail.Chalcogenidoindates: In M/In2S3/S/amine systems, five 1D chains of indium sulfides {[M(en)3]0.5InS2 (M = Co(1), Ni(2)), [Ni(dien)2]0.5[InS2](3), [Ni(dap)3]0.5[InS2] (4) and [Ni(tepa)]2[In4S7(SH)2]·H2O(5)}, and one 3D open framework of indium sulfide (dapH2)3[In10S18] (6), have been solvothermally synthesized by using different organic amine as structure-directing agents or templates. In 1~4, the structures of 1-D indium sulfides consist of [InS2-]n chain built from InS4 tetrahedra sharing opposite edges, but these chains display different conformations. The different organic amines have a significant effect onto the structural modes of 1-D [InS2-]n anionic chains. The 1D {[In4S7(SH)2]4-}n anionic chain in 5 is significantly different from 1D [InQ2-]n chain. The 1D polymeric [In4S9H24-]n chain is constructed by arachno-shaped In4S11 cluster via the edge-sharing mode, the [Ni(tepa)]2+ complex cations are regularly appended to the chain by the In-S-Ni bridges, just like grapes connected in four orientations of chain. The structure of 6 consists of 3D open-framework of supertetrahedral T3 cluster. The 3D {[In10Q18]6-}n (Q = S, Se) type anion is previously obtained in non-chelating amine solvent, but 6 is the first {[In10S18]6-}n type compound with protonated chelating amine as counterion. In M2+/InCl3/Te/amine systems, six 1D chains of telluridoindates [Zn(taa)(μ-tren)0.5][InTe2]Cl(7), [M(en)3]In2Te4·en (M = Ni(8), Co(9)) and [M(en)3]2(en)0.5In4Te8 (M = Mn(10), Fe(11), Zn(12)), have been solvothermally synthesized. The [InTe2-]n chains are built from InTe4 tetrahedra sharing opposite edges with different periodic units, the complex cations and the different number of en molecules can play a crucial role in the formation of different [InTe2-]n chain via the N–H…Te H-bonding interactions.Chalcogenidogallates: Using multi-chelating amine(tepa) as structure-directing agents, two thiogallates {[Ni(tepa)]2SO4}[Ni(tepa)(Ga4S6(SH)4)](13) and [Mn(atep)]Ga2S4 (14) have been solvothermally synthesized. 13 is the first example that a supertetrahedral cluster bonds a [M(amine)m]n+ complex unit, while 14 possesses the topology of 1-D unusually sinusoidal [GaS2-]n chain linked with the complex cation. We have studied Ga/Se/amine and M/Ga/Se/amine solvothermal synthetic systems, and obtained five selenidogallates (H2dap)2Ga4Se8(15), (dienH)3(dienH2)Ga5Se10(16),[(tetaH2)3(teta)]Ga6Se12 (17), [Co(en)3]Ga2Se4 (18) and [Mn(dap)3]0.5GaSe2 (19). In 15, 2-D [Ga4Se84-]n is constructed by the [Ga4Se10]8- units linked together by their four terminal Se atoms in rare D2d symmetry. The structure-directing agents H2dap cations are located above the grooves, similar to the chessboard of chess. The four terminal chalcogen atoms of [Ga4Se10]8- cluster are linked in Td symmetry to form the common 3D network in non-chelating amine solvent. In 16-19, 1D [GaSe2-]n chains display the different conformation, which is related to the different cations.Chalcogenidostannates: Using achiral tepa as structure-directing agents, six achiral chalcogenidostannates [M(tepa)]2(μ-Sn2Q6) (Q=S, M = Fe (20), Co(21), Mn(22); Q = Se, M = Fe (23), Co(24), Mn(25)) and one novel chiral selenidostannate Mn(tepa)Sn3Se7 (26) have been successfully obtained. The flexible achiral tepa coordinates to M2+ions, leading to a chiral center. In 20-25, the [Sn2Q6]4- anion, located at a center of inversion, connects two [M(tepa)]2+ units by the trans terminal Se atoms to form neutral achiral compounds [M(tepa)]2(μ2-Sn2Q6)]. But the polymeric anion {[Sn3Se7]2-}n in 26 is built from pseudo-semicube cluster(Sn3Se4) via edge-bridging, the chiral metal complex cations, just like grapes, are regularly appended to both sides of the chain (grapevine), connected by terminal Se atoms of the anion. Although a number of chalcogenostannates have been obtained by using [M(amine)m]n+ as the structure director, these materials with chiral metal complex ions are all achiral because they are a racemic mix of chiral complex cations. Therefore, 26 is the first chiral selenidostannate.Chalcogenoantimonates: Using dap as structure-directing agents, five chalcogenoantimonates(III) [M(dap)3]Sb4S7(M = Ni2+ (27), Co2+ (28)), [Ni(en)3]Sb2S4 (29),[Ni(dap)3]2(Sb2Se5)]·2H2O(30) and [Zn(dap)3]2(Sb2Se5) (31) have been solvothermally synthesized. In 27 and 28, the polymeric [Sb4S72-]n anion is composed of two SbS3 trigonal pyramids and two SbS4 units, these units are interconnected by corners and edges to build a 2-D puckered layer, the apertures of the large Sb16S16 hetero-rings are filled by two [M(dap)3]2+ complex cations which serve as template ions. As for most of 2-D frameworks with metal complex cations, the cations are usually sandwiched between the anionic layers, fulfilling the charge-balancing role and structure-directing agents, but these counterions are seldom located in the layers. The crystal structure of 29 consists of discrete [Ni(en)3]2+ cations and infinite 1-D [SbS2]- chains, the different crystal structures of the polymeric anions of 27 and 29 might be due to the influence of the methyl group in the dap ligand. The dimeric [Sb2Se5]4- anion in 30 and 31 is formed by corner-sharing SbSe3 trigonal pyramids. In these compounds, the bidentate dap ligand readily chelate divalent transition metal cations to form discrete complex cations. But Cu+ ion is chalcophilic and has less or little tendency to form complex cation with the solvent usually bond directly to the antimony sulfide networks. In the presence of Cu+ ion, two thioantimonates(III) of CuSbQ2 (Q = S(32), Se(33)) was obtained. The 2-D double CuSbQ2 layer structures in 32 and 33 are constructed by Sb2CuQ3 and SbCu2Q3 heterorings, 1,2-diaminopropane(dap) is not incorporated into the final structures of both compounds, therefore, they exhibit semiconductors with band gap of 1.38 eV for 32 and 0.92 eV for 33.Coordination polymers of dimethyl sulfide: Using P2S5 as deoxygenating agents, three coordination polymers containing dimethyl sulfide, [(CuI)4(CH3SCH3)3]n (34) and [CuX(DMS)]n (X = Cl(35), Br(36)) have been successfully synthesized. In 34, the flower-basket-shaped Cu4I4 fragments are bridged by CH3SCH3 molecules to form 2D double-layer. Within the layer, the unusual 1-D infinite helices are constructed by Cu4I4 cluster unit, which is of great practical and theoretical significance. In 35 and 36, the dimeric Cu2X2S4 units are connected by DMS via corner-bridging to form 2D layer.