Synthesis and crystal structure of [(NH4)(6)][Gd2Mo36O112(H2O)(20)]center dot 52H(2)O

A novel compound [(NH4)(6)][Gd2Mo36O112(H2O)(20)]. 52H(2)O (1) was obtained from the reaction of (NH4)(6)Mo7O24. 4H(2)O with GdCl3 at pH = 1.32. The X -ray structural analysis reveals that 1 crystallizes in monoclinic system, space group C2/c, M-r = 6937.77, a = 42.313(1), b=12.924(1), c=26.404(1) An gstrom, beta= 127.07(1)degrees, V=15086.2(6) Angstrom (3), Z=4, D-c = 2.976 g.cm(-3), mu =3.316 mm(-1), F(000) = 12963, the final R = 0.0585 and wR = 0.1490 for 5431 observed reflections. It contains a usual structural unit { Mo-36}, which is linked to two eight-coordinated Gd3+ cations with the Gd-O distances from 2.31(5) to 2.46(5) Angstrom.