LAUSR

The IR and Raman spectra of five AVF3 compounds (A = Li, Na, K, Rb, and Cs) is computed by using an all electron Gaussian type basis set, the hybrid B3LYP functional, and the CRYSTAL code. For the Cs and Rb compounds, only the cubic () spectra are generated, corresponding to the most stable structure. Also for KVF3, NaVF3, and LiVF3, the cubic spectra are computed, for comparison with the Rb and Cs compounds. The spectra corresponding to a minimum of the total energy along the group‐subgroup chain cubic‐tetragonal ‐orthorhombic(Pnma) are also generated for the three lighter compounds. The role of the A cation varies along the series, as expected from the very large mass and ionic radius differences. The deformation of the VF6 octahedra becomes very large for the Li and Na compounds, as documented by the spectra of the Pnma phase, which are very different from the cubic ones.