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Quasiparticle Density-Matrix Representation of Nonlinear TDDFT Response Functions

Oleg Berman·Shaul Mukamel
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Abstract

The time-dependent density functional (TDDFT) equations may be written either for the Kohn-Sham orbitals in Hilbert space or for the single electron density matrix in Liouville space. A collective-oscillator, quasiparticle, representation of the density response of many-electron systems which explicitly reveals the relevant electronic coherence sizes is developed using the Liouville space representation of adiabatic TDDFT. Closed expressions for the nonlinear density-density response are derived, eliminating the need to solve nonlinear integral equations, as required in the Hilbert space formulation of the response.

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Oleg Berman, Shaul Mukamel. 2003-01-09. Quasiparticle Density-Matrix Representation of Nonlinear TDDFT Response Functions. https://doi.org/10.1103/physreva.67.042503

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