One-Dimensional Zinc Selenophosphates: A(2)Znp(2)Se(6) (A = K, Rb, Cs)

The new compounds A(2)ZnP(2)Se(6) (A = K, Rb, Cs) were synthesized via molten salt flux syntheses. The crystals feature one-dimensional 1/infinity[ZnP2Se6](2-) chains charge balanced by alkali metal ions between the chains. K2ZnP2Se6 crystallizes in the monoclinic space group P2(1)/c; cell parameters a = 12.537(3) angstrom, b = 7.2742(14) angstrom, c = 14.164(3) angstrom, beta = 109.63(3)degrees, Z = 4, and V = 1216.7(4) angstrom(3). Rb2ZnP2Se6 and Cs2ZnP2Se6 are isotypic, crystallizing in the triclinic space group P (1) over bar. Rb-2 ZnP2Se6 has cell parameters of a = 7.4944(15) angstrom, b = 7.6013(15) angstrom, c = 12.729(3) angstrom, a = 96.57(3)degrees, beta = 105.52(3)degrees, gamma = 110.54(3)degrees, Z = 2, and V = 636.6(2) angstrom(3). Cs-2 ZnP2Se6 has cell parameters of a = 7.6543(6) angstrom, b = 7.7006(6) angstrom, c = 12.7373(11) angstrom, a = 97.007(7)degrees, beta = 104.335(7)degrees, gamma = 109.241(6)degrees, Z = 2, and V = 669.54(10) angstrom(3).