Dynamical pseudo-Jahn-Teller effect: Time evolution of quantum states above avoided crossing of electronic levels

Abstract

Quantum states above the avoided crossing of electronic levels of a vibronic system with pseudo-Jahn-Teller effect are considered both analytically and numerically. Equations for energies and wave functions of the states are derived. Expansions of these functions over numerically exact vibronic states are obtained and time evolution of the states is found by applying the Fock-Krylov theorem.