Synthesis, structure, and properties of some selenidostannates. II. [(C2H5)(3)NH](2)Sn3Se7 center dot 0,25 H2O and [(C3R7)(2)NH2](4)Sn4Se10 center dot 4 H2O

The new selenidostannate hydrates [(C2H5)(3)NH](2)Sn3Se7.0.25H(2)O (I) and [(C3H7)(2)NH2](4)Sn4Se10. 4H(2)O (II) were synthesized from an aqueous susp ension of triethylammonium (tripropylammonium), tin, selenium I and in addi tion sulfur II at 130 degreesC. I crystallizes at ambient temperature in the monoclinic space group P2(1)/n (a = 2069.3(4) pm, b = 1396.6(3) pm, c = 2342.8(5) pm, beta = 114.68(3)deg rees Z = 8) and is characterized by two different anions, chains from edge- sharing [Se3Se7](2-) units and nets from trigonal SnSe5 bipyramids. II crys tallizes at ambient temperature in the tetragonal space group I4(1)/amd (a = 2150.0(3) pm, c = 1174.4(2) pm, Z = 4) and contains adamantane like [Sn4S e10](4-)-cages. The UV-VIS spectra of the selenidostannates demonstrate that the absorption edges red shift as the dimensionality of the compounds is increased.