On the chemical bond complexity of the H-2(+) in 1-D: The ground-state avoided crossing

Author(s)

Lopez-Castillo, Alejandro ^[1]

Affiliation

^[1] Univ Fed Sao Carlos, Chem Dept, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: COMPUTATIONAL AND THEORETICAL CHEMISTRY; v. 1205, NOV 2021.
• Web of Science Citations: 0

Abstract

The H-2(+) in 1-D is the simplest molecular system possible, where one can study the chemical bond. The 1-D H-2(+) shows complex and different features than that in 3-D. The 1-D model can be usually considered an approximation of 3-D. However, many interesting properties can be studied as the ground state covalent-ionic avoided crossing and chemical bond. We describe the unidimensional H-2(+) in the internuclear axis (axial configuration) and in the perpendicular direction to the internuclear axis (medial configuration). The 1/r (singular) and 1/(r +delta) (smoothed) Coulomb potentials with delta > 0 are also considered in the Hamiltonian operator. The axial configuration can also be divided as ZeZ (proton-electron-proton, electron in between protons) and ZZe (proton-proton-electron, electron not between protons) or equivalently eZZ (electron-proton-proton) sub-configurations. The singular potential (1/r) allows us to obtain diabatic quantum states with defined character. Contrarily, the adiabatic states with avoided crossings are obtained considering smoothed potential (1/(r + delta)). The description of unidimensional H-2(+) in the internuclear axis shows an unusual curve of repulsive electronic energy for ground-state, which appear due to the ZeZ confining configuration. (AU)

• FAPESP's process: 19/12501-0 - Theoretical study of bidimensional systems
• Grantee: Alejandro López Castillo
• Support Opportunities: Regular Research Grants