Hydrothermal syntheses and X-ray crystal structures of three inorganic-organic hybrid materials in a copper vanadium phosphate family:: CuL(VO2)(PO4) (L=4,4′-bipy, 1,10-phen, 2,2′-bipy)

Three inorganic-organic hybrid compounds with the formula CuL(VO2)(PO4), L = 4,4' bipy, 1,10-phen, and 2,2'-bipy, were hydrothermally synthesized at 160 degreesC for 120 h and characterized by single-crystal X-ray diffraction. The use of different bidentate organodiamine ligands in initial reaction systems gave rise to the variety in the structures of the products: Cu(4,4'-bipy)(VO2)(PO4) (1) and Cu(1,10-phen)(VO2)(PO4) (2) crystallize in a monoclinic system with space group C2/c, a = 21.952(4) Angstrom, b = 8.0805(13) Angstrom, c 15.918(2) Angstrom, beta 110.689(4)degrees, and V = 2641.5(7) Angstrom (3), and a = 20.4557(12) Angstrom, b = 11.6231(1) Angstrom, c 14.6422(8) Angstrom, beta = 12?.5520(10)degrees, and V = 2760.0(3) Angstrom (3), respectively. Cu(2,2'- bipy)(VO2)/PO4) (3) crystallizes in a triclinic system with space group P1, a = 5.561(5) Angstrom, b = 10.271(9) Angstrom, c 11.780(9) Angstrom, alpha = 74.31(3)degrees, beta = 79.98(3)degrees, gamma = 85.74(3)degrees, and V = 657.6(9) Angstrom (3). The structures of 1 and 2 possess the same {(VO2O2)(PO4)}(2) four-membered rings, whereas the structure of 3 contains {(VO2)(PO4)}(infinity) infinite chains. In terms of the organic parts, the {Cu(4,4'-bipy)}(infinity) linear chains connect the {(VO2)(PO4)}(2) four-membered rings to build up a 3D framework in 1, whereas the Cu(1,10-phen)(2+) and Cu(2,2'-bipy)(2+) fragments link with the {(VO2)(PO4)}(2) four-membered rings and {(VO2)(PO4)}(2) infinite chains to give two 1D structures of 2 and 3, respectively. Their thermal stabilities were investigated.