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arXiv · 0807.2712

Time-dependent natural orbitals and occupation numbers

H. Appel·E. K. U. Gross
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Abstract

We report equations of motion for the occupation numbers of natural spin orbitals and show that adiabatic extensions of common functionals employed in ground-state reduced-density-matrix-functional theory have the shortcoming of leading always to occupation numbers which are independent of time. We illustrate the exact time-dependence of the natural spin orbitals and occupation numbers for the case of electron-ion scattering and for atoms in strong laser fields. In the latter case, we observe strong variations of the occupation numbers in time.

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H. Appel, E. K. U. Gross. 2008-07-17. Time-dependent natural orbitals and occupation numbers. https://doi.org/10.1209/0295-5075%2F92%2F23001

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