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.