hide
Free keywords:
-
Abstract:
Pb2MgWO6 is an ordered perovskite or elpasolite that undergoes a phase
transition from a cubic paraelectric phase to an orthorhombic
antiferroelectric phase below 310 K. Through an analysis of the
electronic structures of both the high and low temperature phases using
high level band structure methods, the nature of the changes in the
bonding across the phase transition has been examined. The key
stereochemical role of the lone pairs on the lead atoms has been
examined by use of the Electron Localization Function. While the lone
pairs on the lead atoms are smeared out by the near octahedral symmetry
of the lead sites in the high temperature phase, at low temperatures
they localize into the traditional lobes. These changes have been
visualized.
