40 citations · 427 across the 32 of their papers we have counts for
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Response calculations based on an independent particle system with the exact one-particle density matrix: polarizabilities
Klaas J. H. Giesbertz, Oleg V. Gritsenko, Evert Jan Baerends
Recently, we have demonstrated that the problems finding a suitable adiabatic approximation in time-dependent one-body reduced density matrix functional theory can be remedied by i…
Are natural orbitals useful for generating an efficient expansion of the wave function?
Klaas J. H. Giesbertz
We investigate whether the natural orbitals (NOs) minimize , where is a wave function and is a full configuration interaction (CI) approximation to …
Long-range interactions and the sign of natural amplitudes in two-electron systems
Klaas J. H. Giesbertz, Robert van Leeuwen
In singlet two-electron systems the natural occupation numbers of the one-particle reduced density matrix are given as squares of the natural amplitudes which are defined as the ex…
Natural occupation numbers: When do they vanish?
K. J. H. Giesbertz, R. van Leeuwen
The non-vanishing of the natural orbital occupation numbers of the one-particle density matrix of many-body systems has important consequences for the existence of a density matrix…