Comment on “Quantum Confinement and Optical Gaps in Si Nanocrystals”
نویسندگان
چکیده
In a recent Letter [1] Öğüt, Chelikowsky, and Louie (OCL) calculated the optical gap of Si nanocrystals as ε g,OCL = ε qp g,LDA − E e−h Coul, where ε qp g,LDA is the quasi-particle gap in the local-density approximation (LDA) and E Coul is the electron-hole Coulomb energy. They argued that their method produces different results from conventional approaches (e.g. pseudopotential [2]). We show in this Comment that the expression of ε g,OCL
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