Comment on "Quantum Confinement and Optical Gaps in Si Nanocrystals"

TL;DR

This paper critiques a previous method for calculating optical gaps in silicon nanocrystals, highlighting the omission of electron-hole polarization energy and demonstrating that including this correction aligns results with semi-empirical calculations.

Contribution

It identifies a missing electron-hole polarization energy in prior calculations and provides a corrected approach that improves accuracy.

Findings

Corrected optical gaps match semi-empirical results

Omission of polarization energy leads to underestimation

Enhanced understanding of optical properties in Si nanocrystals

Abstract

We show that the method used by Ogut, Chelikowsky and Louie (Phys. Rev. Lett. 79, 1770 (1997)) to calculate the optical gap of Si nanocrystals omits an electron-hole polarization energy. When this contribution is taken into account, the corrected optical gap is in excellent agreement with semi-empirical pseudopotential calculations.