Ab Initio Calculation of Spin Gap Behavior in CaV4O9

Дата и время публикации : 1999-01-24T21:25:19Z

Авторы публикации и институты :
C. Stephen Hellberg
W. E. Pickett
L. L. Boyer
Harold T. Stokes
Michael J. Mehl

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 4 pages; 3 ps figures included in text; Revtex
Первичная категория: cond-mat.mtrl-sci

Все категории : cond-mat.mtrl-sci, cond-mat.str-el

Краткий обзор статьи: Second neighbor dominated exchange coupling in CaV4O9 has been obtained from ab initio density functional (DF) calculations. A DF-based self-consistent atomic deformation model reveals that the nearest neighbor coupling is small due to strong cancellation among the various superexchange processes. Exact diagonalization of the predicted Heisenberg model yields spin-gap behavior in good agreement with experiment. The model is refined by fitting to the experimental susceptibility. The resulting model agrees very well with the experimental susceptibility and triplet dispersion.

Category: Physics