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arXiv · 0710.2057

Optical saturation driven by exciton confinement in molecular-chains: a TDDFT study

Daniele Varsano·Andrea Marini·Angel Rubio
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Abstract

We have identified excitonic confinement in one-dimensional molecular chains (i.e. polyacetylene and H$_2$) as the main driving force for the saturation of the chain polarizability as a function of the number of molecular units. This conclusion is based on first principles time--dependent density functional theory calculations performed with a new derived exchange--correlation kernel. The failure of simple local and semi--local functionals is shown to be related to the lack of memory effects, spatial ultranonlocality, and self--interaction corrections. These effects get smaller as the gap of the system reduces, in which case such simple approximations do perform better.

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Daniele Varsano, Andrea Marini, Angel Rubio. 2007-10-10. Optical saturation driven by exciton confinement in molecular-chains: a TDDFT study. https://arxiv.org/abs/0710.2057

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