Abstract
Ab initio molecular orbital theory and density functional theory calculations were performed on the electronic ground states of the open-shell PS2 molecule and its singly charged ions. A comparison of the optimized molecular structures indicates as the stepwise one-electron reduction of the PS2/+ ion, to yield PS2 and PS2/-, provokes a symmetric elongation of both PS bonds along with a bending of its linear equilibrium geometry. The ionization potential (IP), adiabatic electron affinity (EA(ad)), and atomization energy (AE) of the open-shell PS2 molecule were calculated at different levels of theory. The following values were obtained at the more realistic UMP4SDTQ/6-311 +G(3df)//UHF/6-311 +G(3df) level of theory: IP = 8.32 eV, EA(ad) = 3.03 eV and AE = 12.40 eV. At the same level of theory, the calculated vertical detachment energy (VDE) of the PS2/- anion is 3.22 eV. The donor-acceptor complexes formed in the gas-phase upon interaction of either one or two ammonia molecules with PS2/+ were also investigated. The calculated gas-phase binding energies indicate that the formation of the bis- adduct is favored over that of the mono-adduct by a binding energy gain of about 20 kcal/mol. (C) 2000 Elsevier Science B.V.
Original language | English |
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Pages (from-to) | 127-136 |
Number of pages | 10 |
Journal | Journal of Molecular Structure: THEOCHEM |
Volume | 507 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - 2000 Jul 24 |
Externally published | Yes |
Keywords
- Ab initio MO and DFT calculations
- Donor-acceptor complexes of PS/
- Gas-phase thermochemistry
- Harmonic vibrational frequencies
- PS molecule and its ions
ASJC Scopus subject areas
- Biochemistry
- Condensed Matter Physics
- Physical and Theoretical Chemistry