Applicability of a Valence Force Field Model to the Lattice Vibrations of Trigonal Selenium

概要

論文の詳細を見る
Phonon dispersion curves in the symmetry directions of trigonal selenium are calculated. In addition to the five force constants of the previous paper (J. Phys. Soc. Japan 33 (1972) 12), the sixth force constant K_R' is included in the present work in order to remove a shortcoming of the previous model, an instability at B-point of Brillouin zone. Agreement between the calculated and recently observed dispersion curves for the acoustic branches in low frequency regions as well as for the lower optical branches except the lowest one in the ΓZ and ΓB directions are excellent. Discrepancies for the lowest optical branch and the acoustic branches near zone boundary indicate that the inter-chain interaction can not be represented well enough by such a simple model as the one with the short-range central forces used in the present work.
社団法人日本物理学会の論文
1973-03-05