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| | | #Redirect [[Time-evolution_algorithm]] |
| Description: {{TAG|ALGO}}= timeev calculates the frequency dependent dielectric matrix after the electronic ground state has been determined using the time evolution algorithm (only available in vasp.6)
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| ----
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| The timepropagation algorithm applies an short electric field puls in time, and
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| then follows the evolution of the dipole moments. The Green-Kubo relation
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| then allows to calculate the frequency dependent dielectric response function
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| from the time evolution of the dipole moments <ref name="kubo:57"/>.
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| Details of the implementation are explained in <ref name="sander:prb:2015"/>
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| VASP posses multiple other routines to calculate the frequency dependent dielectric function.
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| The simplest approach uses the independent particle approximation ({{TAG|LOPTICS}}=.TRUE.
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| Furthermore, one can use {{TAG|ALGO}} = TDHF ([[BSE calculations]] equivalent to solving the Casida equation), {{TAG|ALGO}} = GW ([[GW calculations]]).
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| For standard DFT, the timeevolution algorithm is
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| usually fastest, whereas for hybrid functionals {{TAG|ALGO}} = TDHF is
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| usually faster.
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| == Related Tags and Sections ==
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| {{TAG|CSHIFT}},
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| {{TAG|LADDER}},
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| {{TAG|LHARTREE}},
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| {{TAG|NBANDSV}},
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| {{TAG|NBANDSO}}
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| [[BSE calculations]]
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| == References ==
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| <references>
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| <ref name="kubo:57"> [http://journals.jps.jp/doi/10.1143/JPSJ.12.570
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| Ryogo Kubo, Statistical-Mechanical Theory of Irreversible Processes. I. General Theory and Simple Applications to Magnetic and Conduction Problems. In: Journal of the Physical Society of Japan. Band 12, Nr.6, 15. Juni 1957, S.570–586, doi:10.1143/JPSJ.12.57].</ref>
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| <ref name="sander:prb:2015"> [https://journals.aps.org/prb/abstract/10.1103/PhysRevB.92.045209
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| T. Sander, E. Maggio, and G. Kresse, Beyond the Tamm-Dancoff approximation for extended systems using exact diagonalization. Physical Review B, 92, 045209 (2015).]
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| </ref>
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| </references>
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| ----
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| [[The_VASP_Manual|Contents]]
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| [[Category:INCAR]][[Category:Linear response]]
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