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arXiv · 1712.05323

Employing semilocal exchange hole with an application to meta-GGA level screened range separated hybrid functional: A conventional wisdom method

Subrata Jana·Prasanjit Samal
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Abstract

Range separated hybrid density functionals are very successful in describing a wide range of molecular and solid state properties accurately. Range separated hybrid functionals are designed from spherically averaged or system averaged reversed engineered exchange hole. In the present attempt, we employ screened range separated hybrid functional scheme to the meta-GGA rung by using Tao-Mo semilocal exchange hole (or functional). The hybrid functional proposed here utilizes the spherically averaged density matrix expansion based exchange hole in range separation scheme. For slowly varying density correction, we employ range separation scheme only through the local density approximation (LDA) based exchange hole coupled with the slowly varying Tao-Mo enhancement factor through the conventional wisdom technique. Comprehensive performance and testing of the present functional shows, it accurately describes several molecular properties. The most appealing feature of this present screened hybrid functional is that it will be practically very useful in describing solid state properties in meta-GGA level.

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Subrata Jana, Prasanjit Samal. 2017-12-14. Employing semilocal exchange hole with an application to meta-GGA level screened range separated hybrid functional: A conventional wisdom method. https://arxiv.org/abs/1712.05323

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