title: Ab initio quantum Monte Carlo study of the binding of a positron to alkali-metal hydrides.
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.
authors.affiliation: Quantum Chemistry Division, Yokohama City University, Kanazawa-ku, Yokohama, Japan. ykita@yokohama-cu.ac.jp
authors.forename: Yukiumi
authors.initials: Y
authors.lastname: Kita
authors.forename: Ryo
authors.initials: R
authors.lastname: Maezono
authors.forename: Masanori
authors.initials: M
authors.lastname: Tachikawa
authors.forename: Mike D
authors.initials: MD
authors.lastname: Towler
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Needs