Jahn-Teller, pseudo Jahn-Teller, and Renner-Teller effects in systems with fractional charges

► A new approach to handle structural distortions in coordinated molecules. ► Formulas for evaluation of the Jahn-Teller Effect, PJTE and RTE in systems with fractional charges. ► PJTE in coordinated diazene molecule. ► JTE as the origin of a butterfly geometry of coordinated white phosphorus. ► RTE in coordinated acetylene molecule.