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arXiv · 1507.08684

On the basis-set extrapolation

Suresh Chandra·Mohit K. Sharma
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Abstract

A possible solution for the problem of memory-size and computer-time, is the extrapolation of basis-set$^1$. This extrapolation has two exponents $α$ and $β$, corresponding to the HF (reference energy) and the energy of correlations (EC), respectively. For a given system, the exponents are taken as constant$^2$, and potential energy surfaces (PES) are generated. We have found that the values of $α$ and $β$ are not constant, but vary from position to position in the system. How to deal with such situation and get very accurate PES, is discussed.

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Suresh Chandra, Mohit K. Sharma. 2015-07-29. On the basis-set extrapolation. https://arxiv.org/abs/1507.08684

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