We apply a new development of density functional perturbation theory to study the vibrational properties of hydrogen-containing complexes in silicon. A conjugate gradient algorithm within the SIESTA package is used to relax the atomic structure of the complexes. Then, the dynamical matrix of the entire supercell is computed analytically and diagonalized, leading to a complete vibrational spectrum. Results for hydrogen dimers, IH2, VHn (n = 1,2,3,4) and V2H6 defects are presented.
- Local vibrational modes