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New selenidogermanate salts [NH 4] 2[H 2N(CH 3) 2] 2Ge 2Se 6 (1) and [Ni(dien) 2] 2Ge 2Se 5(Se 2) (2) (dien = diethylenetriamine), and a selenidogermanate complex [{Ni(tepa)} 2(μ-Ge 2Se 6)] (3) (tepa = tetraethylenepentamine) were prepared by solvothermal reactions. Compounds 1 and 2 consist of discrete [Ge 2Se 6] 4− and [Ge 2Se 7] 4− anions, and NH $_{4}^{+}$ , [H 2N(CH 3) 2] + and [Ni(dien) 2] 2+ counter cations, respectively. The [Ge 2Se 6] 4− anion is constructed by two tetrahedral GeSe 4 building units via edge-sharing. In 2, two tetrahedral GeSe 4 units are linked by a corner and a Se–Se bond to form a polyselenidogermanate anion [Ge 2Se 7] 4− containing a five-membered ring Ge 2Se 3. The dimeric [Ge 2Se 6] 4− anion acts as a bridging ligand via the trans terminal Se atoms to link two [Ni(tepa)] 2+ cations, resulting in neutral complex 3. The Ni 2+ ion in 2 is coordinated by two tridentate dien ligands, while it is coordinated by a pentadentate tepa ligand and a selenidogermanate anion in 3. The different coordination environments of Ni 2+ ions indicate the influence of the denticity of ethylene polyamines on the formation of selenidogermanates in the presence of transition metal ions. The compounds 1–3 exhibit optical band gaps between 2.06 and 2.35 eV.

A series of polymeric Mn(II)-thioarsenates [Mn(en)3]n[(N2H4)2Mn6(μ6-S)(μ-N2H4)2(μ3-AsS3)4]n (1), [N2H5]n[{Mn(μ-N2H4)2(μ-AsS4)}·0.5en]n (2), [Mn(μ-trien){Mn(μ-N2H4)(μ-AsS3)}2]n (3), [{Mn(N2H4)}2(μ-N2H4)2{Mn(μ-N2H4)2(μ-AsS3)2}]n (4), [Mn3(μ-N2H4)6(μ3-AsS4)(μ2-AsS4)]n (5), and [Mn(NH3)6]n[{Mn(NH3)(μ-AsS4)}2]n (6) were synthesized using a hydrazine-solvothermal method. The thioarsenate units AsS3 and AsS4 coordinate to Mn(II) ions with variable coordination modes, forming a Mn–As–S ternary cluster (1), chains (2, 4–6), and layers (3), respectively. The hydrazine molecules act as inter-cluster, intra-chain and intra-layer bridging ligands to join the Mn(II) ions, resulting in hydrazine hybrid 1-D, 2-D, and 3-D Mn(II)-thioarsenate moieties in 1–5. Compounds 1–6 exhibit tunable semiconducting band gaps varying in the range of 2.19–2.47 eV. Compound 1 displays stronger antiferromagnetic coupling interactions than that of compound 2.

Polymeric lanthanide complexes with thiostannate and polyamine mixed ligands, [Ln(peha)(μ–SnS4H)]n [Ln=La (1a), Nd (1b)] and [{Ln(tepa)(μ–OH)}2(μ–Sn2S6)]nnH2O [Ln=Nd (2a), Sm (2b), Gd (2c), Dy (2d)] (peha=pentaethylenehexamine, tepa=tetraethylenepentamine) were respectively prepared in peha and tepa coordinative solvents by the solvothermal methods. In 1a and 1b, the Ln3+ ions are coordinated by a hexadentate peha ligand forming [Ln(peha)]3+ units. The [SnS4H]3− anion chelates a [Ln(peha)]3+ unit via two S atoms and coordinates to another [Ln(peha)]3+ unit via the third S atom. As a result, the [Ln(peha)]3+ units are connected into coordination polymers [Ln(peha)(μ–SnS4H)]n by an unprecedented tridentate μ–η1,η2–SnS4H bridging ligands. In 2a–2d, the Ln3+ ions are coordinated by a pentadentate tepa ligand, and two [Ln(tepa)]3+ units are joined by two μ–OH bridges to form a binuclear [{Ln(tepa)(μ–OH)}2]4+ unit. Behaving as a bidentate μ–η1, η1–Sn2S6 bridging ligand, the Sn2S6 unit connects [{Ln(tepa)(μ–OH)}2]4+ units into a neutral coordination polymer [{Ln(tepa)(μ–OH)}2(μ–Sn2S6)]n via the trans S atoms. The Ln3+ ions are in distorted monocapped square antiprismatic and bicapped trigonal prismatic environments in [{Ln(peha)(μ–SnS4H)]n and [{Ln(tepa)(μ–OH)}2(μ–Sn2S6)]n, respectively. The denticities of ethylene polyamine play an important role on the formation and complexation of the thiostannate in the presence of lanthanide ions. Compounds 1a–2d show well-defined absorption edges with band gaps between 2.81 and 3.15 eV.

Zinc tellurostannates [{Zn(teta)}2(μ-1κ:2κ-SnTe4)] (1), [{Zn(teta)}3(μ3-1κ:2κ:3κ-SnTe4)]I2 (2), [{Zn(tren)}2(μ-1κ:2κ-Sn2Te6)] (3), and [Zn(dien)2]4(Sn2Te6)1.75(Sn2Te8)0.25·dien (4) were prepared by the reactions of Zn, Sn, and Te with iodine ion assistant in teta and dien. The tetrahedral [SnTe4]4− anion coordinates to two [Zn(teta)]2+ units as a bidentate μ-1κ:2κ-SnTe4 ligand to form the neutral complex 1. It coordinates to three [Zn(teta)]2+ units with a tridentate μ3-1κ:2κ:3κ coordination modes, generating a complex cation [{Zn(teta)}3(μ3-1κ:2κ:3κ- SnTe4)]2+ in 2. In 3, the [Sn2Te6]4− anion joins two [Zn(tren)]2+cations with the trans terminal Te atoms, forming neutral complex 3. The μ-1κ:2κ-SnTe4, μ3-1κ:2κ:3κ-SnTe4, and μ-1κ:2κ-Sn2Te6 ligands to TM centers in 1–3 have not been observed before. Compound 4 contains a normal [Sn2Te6]4− and an abnormal [(Sn2Te6)0.75(Sn2Te8)0.25]4− anions. Compounds 1–4 exhibit narrow band gaps in the range of 1.47–1.98 eV, and a distinct red-shift of the band gaps is observed from 4 to 1−3.

Solvothermal reactions of Ln2O3, As and S in diethylenetriamine (dien) at 170 °C for 6 days afforded two structural types of lanthanide thioarsenates with the general formulae [Ln(dien)2(μ-1κ,2κ2-AsS4)]n [Ln=Sm(1), Eu(2), Gd(3)] and [Ln(dien)2(1κ2-AsS4)] [Ln=Tb(4), Dy(5), Ho(6)]. The Ln2O3 oxides were converted to [Ln(dien)2]3+ complex units in the solvothermal reactions. The As atom binds four S atoms, forming a tetrahedral AsS4 unit. In 1−3, the AsS4 units interconnect the [Ln(dien)2]3+ cations via Ln−S bonds as tridentate μ-1κ,2κ2-AsS4 bridging ligands, resulting in the neutral coordination polymers [Ln(dien)2(μ-1κ,2κ2-AsS4)]n (Ln1). In 4−6, the AsS4 units coordinate with the Ln3+ ion of [Ln(dien)2]3+ as 1κ2-AsS4 chelating ligands to form neutral coordination compounds [Ln(dien)2(1κ2-AsS4)] (Ln2). The Ln3+ ions are in nine- and eight-coordinated environments in Ln1 and Ln2, respectively. The formation of Ln1 and Ln2 is related with ionic size of the Ln3+ ions. Optical absorption spectra showed that 1−6 have potential use as semiconductors with the band gaps in the range 2.18−3.21 eV.

Lanthanide selenidostannates (H3O)n[Ce(tepa)(μ-1κ2:2κ2-Sn2Se6)]n (1), [{Yb(tepa)(μ-OH)}2(μ-1κ:2κ-Sn2Se6)]n·nH2O (2), [Htrien]2[{Ln(trien)(tren)}2(μ-1κ:2κ-Sn2Se6)][Sn2Se6] (Ln=Ce(3), Nd(4)) and [{Yb(dien)2}2(μ-OH)2]Sn2Se6 (5) were solvothermally prepared in different ethylene polyamines. The Sn2Se6 unit connects [Ce(tepa)]3+ and [{Yb(tepa)(μ-OH)}2]4+ fragments with tetradentate μ-1κ2Se1,Se2:2κ2Se5,Se6 and bidentate μ-1κSe1:2κSe5 bridging coordination modes in tepa, to form polymers 1 and 2, respectively. It joins two [Ln(trien)(tren)]3+ fragments as a μ-1κSe1:2κSe5 ligand to form binuclear complexes 3 and 4 in trien. Unlike the Sn2Se6 units in 1–4 that bind with Ln(III) centers as Se-donor ligands, the Sn2Se6 unit in 5 exists as a discrete ion. The syntheses of 1–5 show that the ethylene polyamines play an important role in the complexation of Sn2Se6 ligand with Ln(III) centers. Compounds 1–5 exhibit optical band gaps in the range of 2.09–2.42 eV, which are influenced by the complexation of Sn2Se6 with Ln(III) centers.

New heterometallic thioantimonates(III) [Co(dien)2]HgSb2S5 (1), [Ni(dien)2]HgSb2S5 (2) and [H2dien]HgSb8S14 (3), and a mixed-valent thioantimonate(III,V) [Co(dien)2]2Sb4S9 (4) were solvothermally prepared in diethylenetriamine (dien) solvent from Co(Ni)–Hg–Sb–S, Hg–Sb–S and Co–Sb–S systems, respectively. In 1 and 2, the bimeric subunit Sb2S5 condenses with HgS4 tetrahedron via sharing common S atoms to form an one-dimensional [HgSb2S5]n2n− chain, in which a new μ3-1κ2S1,S5:2κS2:3κS4 bridging mode of the Sb2S5 subunit is obtained. In 3, four SbS3 trigonal pyramids and a linear HgS2 unit condense via sharing S atoms to generate an one-dimensional double-lined [HgSb8S14] n2n− chain. In 4, three SbIIIS3 pyramids and a SbVS4 tetrahedron share common corners to form an one-dimensional mixed-valent [Sb4S9]n4n− anion. The syntheses of 1–4 demonstrated that the Hg2+ ion is easily incorporated into thioantimonate networks, and has a higher affinity to S than that of transition metals. 1–4 exhibit semiconducting properties with optical band gaps in 2.0–2.4 eV.

Polysulfido-thioantimonate [Co(phen)3][Sb4S5(S4)2] (1) and thioantimonates [Co(phen)3]2Sb18S29 (2) and [H3O][Co(phen)3]SbS4·9H2O (3) (phen = 1,10-phenanthroline) were prepared using [Co(phen)3]2+ formed in situ as a structure directing agent in 80% and 50% CH3OH aqueous solution or water solution, respectively. In 1, eight Sb3+ ions are connected by ten μ-S2– and four μ-S42– bridging ligands to form a circular polysulfide thioantimonate anion [Sb8S10(S4)4]4– which contains a sixteen-membered Sb8S8 heteroring. The Sb3+ ions are in trigonal pyramidal SbS3 or trigonal bipyramidal ψ-SbS4 geometries. In 2, sixteen SbS3 and two ψ-SbS4 units are interconnected by sharing S atoms to form a three-dimensional [Sb18S294–]∞ framework containing an interpenetrating channel system, in which the [Co(phen)3]2+ complexes are enclosed. In 3, by O-H···O and O-H···S H-bonding, [SbS4]3–, H2O and H3O+ are interconnected into a {H3O-SbS4-(H2O)9}n2n– anionic layer, which contains a (H2O)6 water cluster. The [Co(phen)3]2+ complexes are located between the layers. The syntheses of 1-3 show the influences of different solvents on the Co/Sb/S/phen system. The optical band gaps of 1-3 are 2.02, 2.11, and 2.27 eV, respectively.