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arXiv · 1603.06605

Improved Optimization for the Cluster Jastrow Antisymmetric Geminal Power and Tests on Triple-Bond Dissociations

Eric Neuscamman
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Abstract

We present a novel specialization of the variational Monte Carlo linear method for the optimization of the recently introduced cluster Jastrow antisymmetric geminal power ansatz, achieving a lower-order polynomial cost scaling than would be possible with a naive application of the linear method and greatly improving optimization performance relative to the previously employed quasi-Newton approach. We test the methodology on highly multi-reference triple-bond stretches, achieving accuracies superior to traditional coupled cluster theory and multi-reference perturbation theory in both the typical example of N$_2$ and the transition-metal-oxide example of [ScO]$^+$.

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Eric Neuscamman. 2016-03-21. Improved Optimization for the Cluster Jastrow Antisymmetric Geminal Power and Tests on Triple-Bond Dissociations. https://arxiv.org/abs/1603.06605

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