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arXiv · 1206.3556

An exactly size consistent geminal power via Jastrow factor networks in a local one particle basis

Eric Neuscamman
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Abstract

The accurate but expensive product of geminals ansatz may be approximated by a geminal power, but this approach sacrifices size consistency. Here we show both analytically and numerically that a size consistent form very similar to the product of geminals can be recovered using a network of location specific Jastrow factors. Upon variational energy minimization, the network creates particle number projections that remove the charge fluctuations responsible for size inconsistency. This polynomial cost approach captures strong many-electron correlations, giving a maximum error of just 1.8 kcal/mol during the double-bond dissociation of H2O in an STO-3G atomic orbital basis.

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Eric Neuscamman. 2012-11-16. An exactly size consistent geminal power via Jastrow factor networks in a local one particle basis. https://doi.org/10.1103/physrevlett.109.203001

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