Abstract:
Two layered vanadyl selenites with the compositions, [DABCOH(2)](0.5)[((VO)-O-IV)(HSeO3)(SeO3)].H2O, I, and [enH(2)][((VO)-O-iv)(2)((VO)-O-V)O-2(SeO3)(3)]-.1.25H(2)O, II, have been prepared by the reaction of NaVO3 with SeO2 or H2SeO4 under hydrothermal conditions in the presence of organic amines. Crystal data: 1, orthorhombic, space group Pbcn (No. 60), a = 6.3152(3) Angstrom, b = 18.1918(8) Angstrom, c = 17.7172(8) Angstrom, V = 2035.4(2) Angstrom(3), Z = 8, R1 (all data) = 0.0368; II, triclinic, space group P (1) over bar (No.2), a = 6.3406(2) Angstrom, b = 10.2085(3) Angstrom, c = 13.2551 (10) Angstrom, alpha = 101.238(2)degrees, beta = 96.503(2)degrees, gamma = 104.332(2)degrees, V = 803.47(4) Angstrom(3), Z = 2, R1 (all data) = 0.0814. While I contains the ladder motif, commonly found in open-framework metal phosphates, 11 is formed by a secondary building unit composed of a V4018 cluster along with SeO3 and VO5 groups. The study demonstrates that the selenite unit can be fruitfully exploited to design interesting open-framework structures.
