DETERMINATION OF COMPLEX STRUCTURES FROM POWDER DIFFRACTION DATA - THE CRYSTAL-STRUCTURE OF LA3TI5AL15O37

The applicability of powder diffraction techniques to structure determ ination has improved substantially in recent times, but it has only be en successfully utilized in the solution of relatively simple structur es of up to 29 atoms in the asymmetric unit. The structure La3Ti5Al15O 37, which has 60 atoms in the asymmetric unit, has been solved using a combination of synchrotron X-ray and neutron powder diffraction. This represents a considerable advance in the size of structure that has b een solved using powder diffraction techniques. The structure of La3Ti 5Al15O37 consists of small regions of simpler structure types in the L a/Ti/Al/O system, interleaved to form a complex 3D network. (C) 1994 A cademic Press, Inc.