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Updated: May 30, 2026

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis
Published on: March 29, 2016
Ab initio quantum Monte Carlo study of the binding of a positron to alkali-metal hydrides
Yukiumi Kita1, Ryo Maezono, Masanori Tachikawa
1Quantum Chemistry Division, Yokohama City University, Kanazawa-ku, Yokohama, Japan. ykita@yokohama-cu.ac.jp
Abstract:
Quantum Monte Carlo methods are used to investigate the binding of a positron to the alkali-metal hydrides, XH (X = Na and K). We obtain positron affinities for the NaH and KH molecules of 1.422(10) eV and 2.051(39) eV, respectively. These are considerably larger than the previous results of 1.035 eV and 1.273 eV obtained from multireference single- and double-excitation configuration interaction calculations. Together with our previous results for [LiH;e(+)] [Y. Kita et al., J. Chem. Phys. 131, 134310 (2009)], our study confirms the strong correlation between the positron affinity and dipole moment of alkali-metal hydrides.
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