Vibronic interaction in a copper oxide cluster

Citation
T. Kato et al., Vibronic interaction in a copper oxide cluster, CHEM PHYS, 271(1-2), 2001, pp. 31-39
Citations number
64
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
CHEMICAL PHYSICS
ISSN journal
0301-0104 → ACNP
Volume
271
Issue
1-2
Year of publication
2001
Pages
31 - 39
Database
ISI
SICI code
0301-0104(20010901)271:1-2<31:VIIACO>2.0.ZU;2-H
Abstract
The orbital vibronic interaction in a D-4h copper oxide cluster Cu4O12H8, w hich is one of the smallest cluster models for the CuO2 sheet of copper oxi de compounds, is investigated to increase our knowledge of high-T-c superco nductors. Only the B-1g, and B-2g vibrational modes can couple to the degen erate e(u) HOMO of CU4O12H8. The orbital vibronic coupling constants of the B-1g and B-2g modes to the e(u) HOMO are calculated and analyzed with the hybrid UB3LYP method that can reasonably describe the anti ferromagnetic in teractions between neighboring copper ions. The B-1g mode of 191 cm(-1) and the B-2g modes of 51 and 505 cm(-1) give very large coupling constants. Th e lowest frequency B-2g mode of 51 cm(-1) most strongly couples to the e(u) HOMO. The HOMO is localized diagonally in the broken-symmetry antiferromag netic state, and therefore it is reasonable that this diamond-shaped distor tion mode significantly couples to the HOMO. (C) 2001 Elsevier Science B.V. All rights reserved.