title: Electronic structure and rovibrational properties of ZnOH in the X̃²A' electronic state: a computational molecular spectroscopy study.
abstract: The three-dimensional ground-state potential energy surface of ZnOH has been calculated ab initio at the MR-SDCI+Q_DK3/[QZP ANO-RCC (Zn, O, H)] level of theory and used as basis for a study of the rovibrational properties carried out by means of the program MORBID (Morse Oscillator Rigid Bender Internal Dynamics). The electronic ground state is  (2)A' (correlating with (2)Σ(+) at the linear configuration). The equilibrium structure has r(e)(Zn-O) = 1.8028 Å, r(e)(O-H) = 0.9606 Å, and ∠e(Zn-O-H) = 114.9°. The Zn-O bond is essentially ionic, with appreciable covalency. The bonding character is compared with those of FeOH (quasi-linear) and CsOH (linear). The rovibrationally averaged structural parameters, determined as expectation values over MORBID wavefunctions, are ⟨r(Zn-O)⟩0 = 1.8078 Å, ⟨r(O-H)⟩0 = 0.9778 Å, and ⟨∠(Zn-O-H)⟩0 = 117°. The Yamada-Winnewisser quasi-linearity parameter is found to be γ0 = 0.84, which is close to 1.0 as expected for a bent molecule. Since no experimental rovibrational spectrum has been reported thus far, this spectrum has been simulated from the ab initio potential energy and dipole moment surfaces. The amphoteric character of ZnOH is also discussed.
authors.affiliation: Department of Chemistry, Faculty of Science, Ochanomizu University, 2-1-1 Otsuka, Bunkyo-ku, Tokyo 112-8610, Japan.
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Hirano
authors.affiliation: Physikalische und Theoretische Chemie, Bergische Universität, D-42097 Wuppertal, Germany.
authors.forename: Mounir Ben Dahman
authors.initials: MB
authors.lastname: Andaloussi
authors.affiliation: Nanosystem Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
authors.forename: Umpei
authors.initials: U
authors.lastname: Nagashima
authors.affiliation: Physikalische und Theoretische Chemie, Bergische Universität, D-42097 Wuppertal, Germany.
authors.forename: Per
authors.initials: P
authors.lastname: Jensen