Structure of the Incommensurate Superlattices of 2H - TaSe sub 2.

摘要

Reinterpretation of the neutron diffraction study of 2H-TaSe sub 2 by Moncton, Axe and DiSalvo (1977) reveals an ambiguity in the sense of the displacements proposed for the commensurate superlattice structure. An attempt is made to resolve this ambiguity by electrostatic and short-range energy calculations of the phase dependence of the energy of the periodic structural distortion wave. There is a fine balance between Se-Se short range repulsion, Ta-Se electrostatic and short-range repulsion and the CDW-Ta ion interaction energy terms. The analysis reveals the phase dependence of the various terms and allows the different contributions to the stability of the distortion waves to be discussed more completely than previously. (Atomindex citation 12:600775)