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arXiv · 0805.0280

Comment on "Self-Purification in Semiconductor Nanocrystals"

M. -H. Du·S. C. Erwin·Al. L. Efros·D. J. Norris
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Abstract

In a recent Letter [PRL 96, 226802 (2006)], Dalpian and Chelikowsky claimed that formation energies of Mn impurities in CdSe nanocrystals increase as the size of the nanocrystal decreases, and argued that this size dependence leads to "self-purification" of small nanocrystals. They presented density-functional-theory (DFT) calculations showing a strong size dependence for Mn impurity formation energies, and proposed a general explanation. In this Comment we show that several different DFT codes, pseudopotentials, and exchange-correlation functionals give a markedly different result: We find no such size dependence. More generally, we argue that formation energies are not relevant to substitutional doping in most colloidally grown nanocrystals.

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M. -H. Du, S. C. Erwin, Al. L. Efros, D. J. Norris. 2008-05-02. Comment on "Self-Purification in Semiconductor Nanocrystals". https://doi.org/10.1103/physrevlett.100.179702

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