THE CRYSTAL-STRUCTURE OF A NEW BOROGERMANOSILICATE ND3BGE1.08SI0.92O10

The structure of Nd3BGe1.08Si0.92O10 has been determined by a single c rystal investigation. The orthorhombic cell parameters are a = 9.845(1 ) angstrom, b = 7.146(1) angstrom, and c = 23.382(2) angstrom. The spa ce group is Pbca (Z = 8). Out of 10,833 measured reflections, 3,099 in dependent reflections (I > 3sigma(I)) have been used in the refinement of the structure. The R factor value is 0.026 (wR = 0.023). The neody mium ions occupy three different sites with eight or nine oxygen bonds in the lattice. The germanium and silicon ions are located in a disto rted tetrahedral environment. The boron atom coordination is triangula r with a shorter B-O distance of 1.384 angstrom. (C) 1994 Academic Pre ss, i.c.