CRYSTAL STRUCTURE OF MANGANESE METAGERMANATE, MNGEO3

The crystal structure of manganese metagermanate, MnGe03, has been refined. Two independent sets of three-dimensional x-ray intensities were measured. The crystallographic data are: α = 19.267Å, b = 9.248Å, c = 5.477Å; Z = 16 and space group Pbca. The compound is isotypic with enstatite, MgSiO3. Using the positional parameters of enstatite as a starting point, the structure was refined to RF = 0.08. The essential feature of the structure is the linkage of GeO4 tetrahedra to form single chains running parallel to the c axis. The chains are bound together by manganese octahedra. There are two crystallographically different chains, arranged with the vertices of alternate tetrahedra pointing in opposite directions. Average Ge-O and Mn-0 distances are 1.75 Â and 2.21 Â, respectively. © 1969, Walter de Gruyter. All rights reserved.