Investigation of vibrational characteristics of fayalite

This study presents the findings of a vibrational analysis of fayalite (Fe₂SiO₄) employing normal coordinate analysis rooted in a short-range force model. By employing this methodology, the Raman and IR wave numbers for Fe₂SiO₄ were thoroughly investigated. The lattice dynamical calculations integrated fifteen stretching and ten bending force constants within the framework of Wilson's GF matrix method. Notably, the outcomes reveal a strong concurrence between the optical vibrational modes computed at the zone center and the existing findings. Furthermore, a comprehensive analysis of mode assignment for the calculated Raman and infrared phonons has been conducted. The study culminates in a theoretical examination of the vibrational phonons, followed by an insightful analysis of potential energy distribution, underscoring the contribution of interatomic forces to the calculated Raman and infrared phonons. (author)