TY - JOUR

T1 - Ab Initio Reconstruction of Interatomic Potential for the Ground Electronic State of CO Molecule

AU - Мешков, Владимир Владимирович

AU - Пазюк, Елена Александровна

AU - Столяров, Андрей Владиславович

AU - Усов, Даниил Павлович

AU - Рыжков, Антон Михайлович

AU - Савельев, Игорь Михайлович

AU - Кожедуб, Юрий Сергеевич

AU - Мосягин, Николай Сергеевич

AU - Шабаев, Владимир Моисеевич

PY - 2023/10/1

Y1 - 2023/10/1

N2 - The energy of the ground state of the carbon monoxide molecule has been calculated by multi-configuration methods of self-consistent field (MC-SCF), configuration interaction (MR-CI+Q), and the averaged coupled pair functional (MR-ACPF) on a detailed grid and in a wide range of internuclear distances 0.1 < R < 17.0 Å. The scalar relativistic correction is systematically taken into account using the effective second-order Douglas–Krol–Hess (DKH) Hamiltonian. Quantum electrodynamic (QED) correction to mass invariant potential has been estimated for the first time using a model one-electron operator, which has been built independently for each atom. The calculations have been carried out using the family of correlation-consistent aug-cc-pwCVnZ-DK (n = 3, 4, 5) bases for both atoms followed by extrapolation to the complete basis set (CBS) in the framework of the empirical three-point scheme. The resulting potential has been found to be very close to its semi-empirical counterpart near the equilibrium position and at the dissociation limit. It is expected that the most significant clarification ab initio potential corresponds to the intermediate region 2.0 < R < 4.5 Å, where reliable experimental data are not yet available.

AB - The energy of the ground state of the carbon monoxide molecule has been calculated by multi-configuration methods of self-consistent field (MC-SCF), configuration interaction (MR-CI+Q), and the averaged coupled pair functional (MR-ACPF) on a detailed grid and in a wide range of internuclear distances 0.1 < R < 17.0 Å. The scalar relativistic correction is systematically taken into account using the effective second-order Douglas–Krol–Hess (DKH) Hamiltonian. Quantum electrodynamic (QED) correction to mass invariant potential has been estimated for the first time using a model one-electron operator, which has been built independently for each atom. The calculations have been carried out using the family of correlation-consistent aug-cc-pwCVnZ-DK (n = 3, 4, 5) bases for both atoms followed by extrapolation to the complete basis set (CBS) in the framework of the empirical three-point scheme. The resulting potential has been found to be very close to its semi-empirical counterpart near the equilibrium position and at the dissociation limit. It is expected that the most significant clarification ab initio potential corresponds to the intermediate region 2.0 < R < 4.5 Å, where reliable experimental data are not yet available.

KW - ab initio calculations

KW - carbon monoxide

KW - electronic structure

KW - interatomic potential

KW - relativistic and quantum electrodynamic correction

UR - https://www.mendeley.com/catalogue/a42fe902-024f-35b1-8e65-4d4ade519570/

U2 - 10.1134/s0036024423100163

DO - 10.1134/s0036024423100163

M3 - Article

VL - 97

SP - 2165

EP - 2170

JO - Russian Journal of Physical Chemistry A

JF - Russian Journal of Physical Chemistry A

SN - 0036-0244

IS - 10

ER -