A. Gupta, R. Gross, et al.
SPIE Advances in Semiconductors and Superconductors 1990
The long-range contribution to the phonon dynamical matrix for bcc Ba is calculated from first principles using a perturbative tight-binding formulation of the electron-ion interaction. This contribution gives rise to excellent agreement with the anomalous neutron-scattering spectrum in which the longitudinal mode is found to lie at lower frequencies than the transverse mode in the [100] direction. The short-range contribution is treated within a force-constant model and is not responsible for anomalous behavior in the spectrum. In addition, p-d and d-d mixing terms in the electron-phonon matrix elements form the majority contribution to the dynamical matrix, suggesting that Ba behaves as a transition metal with regard to its electron-phonon interaction. This is similar to previous results obtained from nonperturbative calculations of the total crystal energy. © 1988 The American Physical Society.
A. Gupta, R. Gross, et al.
SPIE Advances in Semiconductors and Superconductors 1990
Kafai Lai, Alan E. Rosenbluth, et al.
SPIE Advanced Lithography 2007
Shiyi Chen, Daniel Martínez, et al.
Physics of Fluids
S. Cohen, T.O. Sedgwick, et al.
MRS Proceedings 1983