Eur. Phys. J. D 35, 467-477 (2005)
https://doi.org/10.1140/epjd/e2005-00079-7

Importance of electronic self-consistency in the TDDFT based treatment of nonadiabatic molecular dynamics

¹ Dept. of Theoretical Physics, University of Paderborn, 33098 Paderborn, Germany
² German Cancer Research Center, Dept. Molecular Biophysics, 69120 Heidelberg, Germany
³ Chemistry and Materials Science, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA

Corresponding author: ^a t.niehaus@dkfz.de

Received: 24 February 2005
Revised: 7 April 2005
Published online: 7 June 2005

Abstract

A mixed quantum-classical approach to simulate the coupled dynamics of electrons and nuclei in nanoscale molecular systems is presented. The method relies on a second order expansion of the Lagrangian in time-dependent density functional theory (TDDFT) around a suitable reference density. We show that the inclusion of the second order term renders the method a self-consistent scheme and improves the calculated optical spectra of molecules by a proper treatment of the coupled response. In the application to ion-fullerene collisions, the inclusion of self-consistency is found to be crucial for a correct description of the charge transfer between projectile and target. For a model of the photoreceptor in retinal proteins, nonadiabatic molecular dynamics simulations are performed and reveal problems of TDDFT in the prediction of intra-molecular charge transfer excitations.