Local-density approximation: Difference between revisions

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m Spin polarization: WP:CHECKWIKI errors fixed + general fixes using AWB (8961)
In the previous version of the article references 5 and 12 were the same.
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* Vosko-Wilk-Nusair (VWN) <ref name="vwn">{{cite journal | title = Accurate spin-dependent electron liquid correlation energies for local spin density calculations: a critical analysis | author = S. H. Vosko, L. Wilk and M. Nusair | journal = Can. J. Phys. | volume = 58 | pages = 1200 | year = 1980 | doi = 10.1139/p80-159 |bibcode = 1980CaJPh..58.1200V | issue = 8 }}</ref>
 
* Perdew-Zunger (PZ81) <ref name="pz81">{{cite journal | title = Self-interaction correction to density-functional approximations for many-electron systems | author = J. P. Perdew and A. Zunger | journal = Phys. Rev. B | volume = 23 | pages = 5048 | year = 1981 | doi = 10.1103/PhysRevB.23.5048 |bibcode = 1981PhRvB..23.5048P | issue = 10 }}</ref>
 
* Cole-Perdew (CP) <ref>{{cite journal | title = Calculated electron affinities of the elements | author = L. A. Cole and J. P. Perdew | journal = Phys. Rev. A | volume = 25 | pages = 1265 | year = 1982 | doi = 10.1103/PhysRevA.25.1265 |bibcode = 1982PhRvA..25.1265C | issue = 3 }}</ref>
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:<math>v_{xc}^{\mathrm{LDA}}(\mathbf{r}) = \frac{\delta E^{\mathrm{LDA}}}{\delta\rho(\mathbf{r})} = \epsilon_{xc}(\rho(\mathbf{r})) + \rho(\mathbf{r})\frac{\partial \epsilon_{xc}(\rho(\mathbf{r}))}{\partial\rho(\mathbf{r})}\ .</math>
 
In finite systems, the LDA potential decays asymptotically with an exponential form. This is in error; the true exchange-correlation potential decays much slower in a Coulombic manner. The artificially rapid decay manifests itself in the number of Kohn-Sham orbitals the potential can bind (that is, how many orbitals have energy less than zero). The LDA potential can not support a Rydberg series and those states it does bind are too high in energy. This results in the [[HOMO]] energy being too high in energy, so that any predictions for the [[ionization potential]] based on [[Koopman's theorem]] are poor. Further, the LDA provides a poor description of electron-rich species such as [[anion]]s where it is often unable to bind an additional electron, erroneously predicating species to be unstable.<ref>{{cite book|last=Fiolhais|first=Carlos|coauthors=Nogueira, Fernando; Marques Miguel|title=A Primer in Density Functional Theory|publisher=Springer|year=2003|isbn=978-3-540-03083-6|page=60}}</ref><ref>{{cite journal|lastname=Perdew|first=J. P. |coauthors=Zunger, Alex |year=1981|title=Self-interaction correction to density-functional approximations for many-electron systems|journal=Phys. Rev. B|volume=23|issue=10|pages=5048–5079|doi=10.1103/PhysRevB.23.5048 |bibcode = 1981PhRvB..23.5048P }}<"pz81"/ref>
 
== References ==