Universal dynamical steps in the exact time-dependent exchange-correlation potential.
We show that the exact exchange-correlation potential of time-dependent density-functional theory displays dynamical step structures that have a spatially nonlocal and time nonlocal dependence on the density. Using one-dimensional two-electron model systems, we illustrate these steps for a range of nonequilibrium dynamical situations relevant for modeling of photochemical or physical processes: field-free evolution of a nonstationary state, resonant local excitation, resonant complete charge transfer, and evolution under an arbitrary field. A lack of these steps in the usual approximations yields inaccurate dynamics, for example, predicting faster dynamics and incomplete charge transfer.
Department of Physics and Astronomy, Hunter College and the Graduate Center of the City University of New York, 695 Park Avenue, New York, New York 10065, USA.
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P
Elliott
J I
JI
Fuks
A
A
Rubio
N T
NT
Maitra
D055598:Chemical Phenomena; D004583:Electrons; D007700:Kinetics; D008956:Models, Chemical; D055668:Photochemical Processes; D013816:Thermodynamics