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arXiv · 1109.3341

Calculating optical absorption spectra for large systems using linear-scaling density-functional theory

Laura E. Ratcliff·Nicholas D. M. Hine·Peter D. Haynes
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Abstract

A new method for calculating optical absorption spectra within linear-scaling density-functional theory (LS-DFT) is presented, incorporating a scheme for optimizing a set of localized orbitals to accurately represent unoccupied Kohn-Sham states. Three different schemes are compared and the most promising of these, based on the use of a projection operator, has been implemented in a fully-functional LS-DFT code. The method has been applied to the calculation of optical absorption spectra for the metal-free phthalocyanine molecule and the conjugated polymer poly(para-phenylene). Excellent agreement with results from a traditional DFT code is obtained.

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Laura E. Ratcliff, Nicholas D. M. Hine, Peter D. Haynes. 2011-09-15. Calculating optical absorption spectra for large systems using linear-scaling density-functional theory. https://doi.org/10.1103/physrevb.84.165131

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