TY - JOUR

T1 - Theoretical study of the alkali hydride anions XH–(X = Li, Na, and K)

AU - Zeid, Israa

AU - El-Kork, Nayla

AU - Al Shawa, Sally

AU - Korek, Mahmoud

N1 - Funding Information:
This publication is based upon work supported by the Khalifa University of Science and Technology under Award No. CIRA-2019-054 . The authors would like to acknowledge the use of MASDAR High power computer, Khalifa University Nuclear Engineering Department High power computer and Ankabut High Power computer for the completion of their work. Also, the authors would like to acknowledge Quantemol team for pursuing the R-Matrix method calculations.
Funding Information:
This publication is based upon work supported by the Khalifa University of Science and Technology under Award No. CIRA-2019-054. The authors would like to acknowledge the use of MASDAR High power computer, Khalifa University Nuclear Engineering Department High power computer and Ankabut High Power computer for the completion of their work. Also, the authors would like to acknowledge Quantemol team for pursuing the R-Matrix method calculations.
Publisher Copyright:
© 2020

PY - 2020/10/1

Y1 - 2020/10/1

N2 - The electronic structure of the alkali hydride anions (LiH-, NaH-, and KH-), has been investigated via ab initio CASSCF/(MRCI + Q) and R-Matrix method calculations. Comparison between the results of the two calculation methods show that the pure bound state method may be unsuitable for the calculation of the electronic states of LiH- molecule, as the potential energy curves that it presents may be spurious. The adiabatic potential energy curves and the dipole moment curves of the low-lying electronic states of alkali hydride anionic molecules are investigated in the representation 2s+1Ʌ(+/-) where the percentage ionic character fionic around the equilibrium position of the ground state X2Σ+ has been calculated. Additionally, the spectroscopic constants Te, Re, ωe, Be, the dipole moment µe, and the dissociation energy De were computed for the bound states of the two molecules NaH- and KH-. The transition dipole moment curves for the lowest 2Σ+– 2Π transition have been also presented along with their Franck-Condon factor (FCF). A rovibrational study has been performed using the canonical functions approach in order to study the nuclear motion and find the rovibrational constants for the ground and several excited states. The diagonal Franck-Condon factor f00 may provide efficient routes for the formation of cold and ultracold molecules.

AB - The electronic structure of the alkali hydride anions (LiH-, NaH-, and KH-), has been investigated via ab initio CASSCF/(MRCI + Q) and R-Matrix method calculations. Comparison between the results of the two calculation methods show that the pure bound state method may be unsuitable for the calculation of the electronic states of LiH- molecule, as the potential energy curves that it presents may be spurious. The adiabatic potential energy curves and the dipole moment curves of the low-lying electronic states of alkali hydride anionic molecules are investigated in the representation 2s+1Ʌ(+/-) where the percentage ionic character fionic around the equilibrium position of the ground state X2Σ+ has been calculated. Additionally, the spectroscopic constants Te, Re, ωe, Be, the dipole moment µe, and the dissociation energy De were computed for the bound states of the two molecules NaH- and KH-. The transition dipole moment curves for the lowest 2Σ+– 2Π transition have been also presented along with their Franck-Condon factor (FCF). A rovibrational study has been performed using the canonical functions approach in order to study the nuclear motion and find the rovibrational constants for the ground and several excited states. The diagonal Franck-Condon factor f00 may provide efficient routes for the formation of cold and ultracold molecules.

KW - Ab initio calculation

KW - Dipole moments

KW - Electronic structure

KW - Franck-Condon factor

KW - Laser coolin

KW - Potential energy curves

KW - Rovibrational calculations

KW - Spectroscopic constants

UR - http://www.scopus.com/inward/record.url?scp=85087315079&partnerID=8YFLogxK

U2 - 10.1016/j.chemphys.2020.110825

DO - 10.1016/j.chemphys.2020.110825

M3 - Article

AN - SCOPUS:85087315079

SN - 0301-0104

VL - 538

JO - Chemical Physics

JF - Chemical Physics

M1 - 110825

ER -