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Accurate Ab Initio Calculation of Molecular Constants



Svetlana A. Kotochigova, I Tupitsyn


The valence bond method and advanced computational technique are used to perform all-electron ab initio calculations of the electronic structure of diatomic molecules. The basic idea behind the method is to expand the molecular wavefunction in terms of Hartzee-Fock orbitals of the composing atoms. Full Cl within this nonorthogonal basis leads to a high accuracy for the electronic structure calculation. The code generates molecular constants such as dissociation and ionization energies, electronic equilibrium bond distance, vibrational and rotational constants with an uncertainty of a few percent. This uncertainty is estimated from a comparison between our results with both experimental and other theoretical investigations for a number of monhydride molecules.
Journal of Research (NIST JRES) -
103 No. 2


AgH+ molecule, diatomic molecule, dissociation energy, equilibrium bond distance, molecular constants, OH molecule, valence-bond method, vibrational and rotational constants


Kotochigova, S. and Tupitsyn, I. (1998), Accurate Ab Initio Calculation of Molecular Constants, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 18, 2024)


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Created March 1, 1998, Updated February 17, 2017