Nuclear distortion of the equidistant arrangement in trans-polyacetylene, (CH)x

✍ Scribed by M. Kertész; J. Koller; A. Ažman

• Publisher: John Wiley and Sons
• Year: 1980
• Tongue: English
• Weight: 299 KB
• Volume: 18
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/qua.560180240

✦ Synopsis

Abstract

The occurrence of broken‐symmetry Hartree‐Fock solutions may indicate instability of the lattice depending on the symmetry of the charge‐density wave (CDW). In case of polyacetylene, (CH)~x~, we have found such solutions having an off‐diagonal CDW. It is pointed out that this sort of instability is principally different from the Peierls instability. The importance of correct (symmetrical) cutoff of interactions in direct space (“finite neighbor's approximation”) is emphasized. A basic difference in the potential‐energy curve of trans‐(CH)~x~ and the isoelectronic (HCN)~x~ around the equidistant configuration is shown.