## Current-Dependent Exchange-Correlation Potential for Dynamical Linear Response Theory

##### Abstract

The frequency-dependent exchange-correlation potential, which appears in the usual Kohn- Sham formulation of a time-dependent linear response problem, is a strongly nonlocal functional of the density, so that a consistent local density approximation generally does not exist. This problem can be avoided by choosing the current density as the basic variable in a generalized Kohn-Sham theory. This theory admits a local approximation which, for fixed frequency, is exact in the limit of slowly varying densities and perturbing potentials.

##### Citation

Phys. Rev. Lett. 77, 2037-2040 (1996)