Tunneled intergrowth structures in the Ga2O3-In2O3-SnO2 system

The structures of several Ga2O3-In2O3-SnO2 phases were investigated using h igh-resolution electron microscopy, X-ray diffraction, and Rietveld analysi s of time-of-flight neutron diffraction data. The phases, expressed as Ga(4 -4)xIn(4x)Sn(n-4)O(2n-2) (n = 6 and 7-17, odd), are intergrowths between th e beta-gallia structure of (Ga, In)(2)O-3 and the rutile structure of SnO2. Samples prepared with n greater than or equal to 9 crystallize in C2/m and are isostructural with intergrowths in the Ga2O3TiO2 system. Samples prepa red with n = 6 and n = 7 are members of an alternative intergrowth series t hat crystallizes in P2/m, Both intergrowth series are similar in that their members possess 1-D tunnels along the b axis. The difference between the t wo series is described in terms of different crystallographic sheer plane o perations (CSP) on the parent futile structure. (C) 2000 Academic Press.