Low-dimensional sulfoantimonates with metal complexes as counterions.: Hydrothermal synthesis and properties of [M(en)3]Sb2S4 (M = Co, Ni) and [M(en)3]Sb4S7 (M = Fe, Ni)

[M(en)(3)]Sb2S4 (M = Co, Ni) and [M(en)(3)]Sb4S7 (M = Fe, Ni) were prepared from the MX2/Na3SbS3/en system (X = Cl, Br; en ethylenediamine) under hydrothermal conditions. Orange-yellow [Ni(en)(3)]Sb2S4 (1) crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 10.538(2) Angstrom, b = 14.360(4) Angstrom, c = 12.434(5) Angstrom, beta = 99.93(2)degrees, and Z = 4. Green-yellow [Co(en)(3)]Sb2S4 (2) crystallizes as a superstructure of 1 with a = 21.131(4) A, b = 14.619(2) Angstrom, c = 12.540(2) Angstrom, beta = 100.50(1)degrees, and Z = 8. The antimony sulfide frameworks in 1 and 2 consist of SbS3 pyramids sharing two corners to form 1/infinity[SbS2](-) chains. Orange-yellow [Ni(en)(3)]Sb4S7 (3) crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 9.930(1) Angstrom, b = 14.212(2) Angstrom, c = 17.242(2) Angstrom, beta = 102.55(1)degrees, and Z = 4. The 1/infinity[Sb4S7](2-) chains are formed by corner-sharing SbS3 units. Three of these pyramids are arranged to cyclic Sb3S6 trimers which share two of the three exocyclic S-atoms with the fourth SbS3 units to form infinite chains. [Fe(en)(3)]Sb4S7 (4) is isostructural to 3. In all four compounds the tris(ethylenediamine)metal(II) complexes act as counterions. The thermal, magnetic and optical properties of compounds 1-4 are reported.