Phonon spectra and superconductivity of the BiS2-based compounds LaO1−xFxBiS2
Using the density-functional perturbation theory with structural optimization, we investigate the electronic structure, phonon spectra, and superconductivity of the BiS2-based layered compounds LaO1−xFxBiS2. For LaO0.5F0.5BiS2, the calculated electron-phonon coupling constant is equal to λ = 0.8, and the obtained Tc 9.1 K is very close to its experimental value, indicating that it is a conventional electron-phonon superconductor.