Ab initiomolecular dynamics in adaptive coordinates

We present a formulation of ab initio molecular dynamics that exploits the efficiency of plane waves in adaptive curvilinear coordinates, and thus provides an accurate treatment of first-row elements. The method is used to perform a molecular-dynamics simulation of the CO₂ molecule, and allows the reproduction of detailed features of its vibrational spectrum such as the splitting of the Raman σg⁺ mode caused by Fermi resonance. This approach opens the way to highly accurate ab initio simulations of organic compounds.