Abstract
We present a first principles investigation of the lattice dynamics and electron-phonon coupling of the superconductor and the isostructural within the framework of density functional perturbation theory using a mixed-basis pseudopotential method. Complete phonon dispersion curves and Eliashberg functions are calculated for both systems. The main differences are related to high frequency in-plane boron vibrations, which are strongly softened in and exhibit an exceptionally strong electron-phonon coupling. We also report on Raman measurements, which support the theoretical findings. Implications for the superconducting transition temperature are briefly discussed.
- Received 15 March 2001
DOI:https://doi.org/10.1103/PhysRevLett.86.5771
©2001 American Physical Society