Vibrational Spectroscopy of Minerals through Ab Initio Methods

This chapter provides examples that demonstrate the usefulness of ab initio (first principles) simulation in analysing the lattice dynamics and vibrational spectroscopic response of minerals. It focuses on the details of vibrational spectroscopies, namely, infrared, Raman and related techniques, as modelled through first principles methods. The chapter shows how the various tools and methods can be successfully applied to investigate the vibrational properties of mineral systems. Minerals belonging to diverse groups (carbonates, pyroxenes, oxides and hydroxides) are considered, so as to include a variety of compositions, structural motifs and physical properties. In the past few years, quantum mechanical ab initio schemes have been successfully applied to make crystal structural predictions and to unambiguously determine the atomic structure of minerals and solid-state systems. In this context, computing the vibrational spectrum provides information about the topography of the PES around the equilibrium position, as normal modes are obtained directly from second derivatives