Partial-wave decomposition of the one-electron properties of the LiH molecule computed with explicitly correlated basis sets

Abstract

Two one-electron properties of the LiH molecule in its ground state at the internuclear distance of 3.015 bohr, namely the number of electrons and their kinetic energy, are decomposed into contributions due to projections (described by the quantum number m) of individual angular momenta onto the molecular axis. For sufficiently accurate electronic wavefunctions obtained with explicitly correlated Gaussian basis sets, the results of these partial-wave decompositions are found to obey the asymptotics valid at $|m|\to \mathrm{\infty }$ that stem from the off-diagonal cusp in the one-electron reduced density matrix. It turns out that the kinetic energy may be accurately extrapolated to the complete-basis-set limit, even if only the contributions pertaining to small values of $|m|$ are available.

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No potential conflict of interest was reported by the author(s).

Additional information

Funding

The research carried out by Krzysztof Strasburger was supported by the Department of Physical and Quantum Chemistry of Wrocław University of Science and Technology. The research carried out by Jerzy Cioslowski was financed by the National Science Center (Poland) under grant 2018/31/B/ST4/00295. Most calculations have been carried out at Wrocław Center for Networking and Supercomputing (WCSS, http://wcss.pl).