Quadratic integrand double-hybrid made spin-component-scaled.

J Chem Phys

CompuNet, Istituto Italiano di Tecnologia, via Morego 30, I-16163 Genoa, Italy.

Published: March 2016

We propose two analytical expressions aiming to rationalize the spin-component-scaled (SCS) and spin-opposite-scaled (SOS) schemes for double-hybrid exchange-correlation density-functionals. Their performances are extensively tested within the framework of the nonempirical quadratic integrand double-hybrid (QIDH) model on energetic properties included into the very large GMTKN30 benchmark database, and on structural properties of semirigid medium-sized organic compounds. The SOS variant is revealed as a less computationally demanding alternative to reach the accuracy of the original QIDH model without losing any theoretical background.

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http://dx.doi.org/10.1063/1.4944465DOI Listing

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