Band-decomposed charge densities: Difference between revisions

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#REDIRECT [[Partial_charge_densities_and_STM_simulations]]
#REDIRECT [[Partial_charge_densities_and_STM_simulations]]


The partial (band-decomposed) charge density can be used to analyze the contributions of different orbitals or energy ranges to a specific region in real space. It helps in gaining insight and visualizing electronic, magnetic, or transport properties, and is especially important when simulating scanning tunneling microscopy (STM) images.
<!--The partial (band-decomposed) charge density can be used to analyze the contributions of different orbitals or energy ranges to a specific region in real space. It helps in gaining insight and visualizing electronic, magnetic, or transport properties, and is especially important when simulating scanning tunneling microscopy (STM) images.
In VASP, the calculation of partial charges is a quick post-processing step that is selected by setting {{TAG|LPARD}} = .TRUE. in the {{FILE|INCAR}} file. It is necessary to provide a {{FILE|WAVECAR}} from a converged ground state calculation as an input file. To select the contributing '''k''' points and bands, various options exist, which can be selected via the {{TAG|NBMOD}}, {{TAG|IBAND}}, {{TAG|EINT}}, and {{TAG|KPUSE}} tags.
In VASP, the calculation of partial charges is a quick post-processing step that is selected by setting {{TAG|LPARD}} = .TRUE. in the {{FILE|INCAR}} file. It is necessary to provide a {{FILE|WAVECAR}} from a converged ground state calculation as an input file. To select the contributing '''k''' points and bands, various options exist, which can be selected via the {{TAG|NBMOD}}, {{TAG|IBAND}}, {{TAG|EINT}}, and {{TAG|KPUSE}} tags.
{{NB|mind|All charge densities, including the band-decomposed charge densities, are symmetrized using both the space and point group symmetries. However, when calculating partial charge from selected '''k''' points, this can lead to wrong results due to wrong '''k''' point weights. In that case, the symmetry must be turned off during the initial ground state calculation from which the WAVECAR is generated, as well as during the subsequent band-decomposed charge density calculation.}}
{{NB|mind|All charge densities, including the band-decomposed charge densities, are symmetrized using both the space and point group symmetries. However, when calculating partial charge from selected '''k''' points, this can lead to wrong results due to wrong '''k''' point weights. In that case, the symmetry must be turned off during the initial ground state calculation from which the WAVECAR is generated, as well as during the subsequent band-decomposed charge density calculation.}}
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[[Category:Charge density]][[Category:Howto]][[Category:Electronic ground-state properties]]
[[Category:Charge density]][[Category:Howto]][[Category:Electronic ground-state properties]]-->

Latest revision as of 11:04, 20 December 2024