Using the linear response theory, the vibrational and dielectric properties are calculated for c-BN, w-BN and h-BN. Calculations of the zone-center optical-mode frequencies (including LO-TO splittings) are reported. All optic modes are identified and agreement of theory with experiment is excellent. The static dielectric tensor is decomposed into contributions arising from individual infrared-active phonon modes. It is found that all of the structures have a smaller lattice dielectric constant than that of electronic contribution. Finally, the infrared reflectance spectrums are presented. Our theoretical results indicate that w-BN shows a similar reflectivity spectrum as c-BN. It is difficult to tell the wurtzite structure from the zinc blende phase by IR spectroscopy.
@article{arxiv.1108.0154,
title = {Infrared Reflectance Spectrum of BN Calculated from First Principles},
author = {Yongqing Cai and Litong Zhang and Qingfeng Zeng and Laifei Cheng and Yongdong Xu},
journal= {arXiv preprint arXiv:1108.0154},
year = {2011}
}