Premium
Dioxygen spectra and bioactivation
Author(s) -
Minaev Boris F.,
Murugan N. Arul,
Ågren Hans
Publication year - 2013
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.24390
Subject(s) - chemistry , quadrupole , spectral line , atomic physics , spin (aerodynamics) , dipole , absorption spectroscopy , molecular physics , physics , organic chemistry , astronomy , thermodynamics , quantum mechanics
Intensities of spin‐forbidden transitions in electronic absorption and emission spectra of molecular oxygen are analyzed in order to understand the key mechanisms of spin‐states mixing induced by spin‐orbit coupling (SOC) and the ways to overcome spin prohibition for various photophysical and biochemical processes. Multireference configuration interaction calculations with SOC account are used to generalize spin‐selection rules for the oxygen atmospheric and Herzberg bands in free O 2 molecule and in collision complexes. Intensity enhancement of the atmospheric a 1 Δ g → X 3 Σ g − , b 1 Σ g + → X 3 Σ g − , and Noxon b 1 Σ g + → a 1 Δ g transitions upon bimolecular collisions are compared with those for Herzberg III transitions A ′3 Δ u ← X 3 Σ g − . Electric quadrupole, dipole, and magnetic approximations are used for transition probability calculations. Intensity distribution in rotational lines is also considered. With this background, we propose some simple spin‐selection rules for dioxygen activation in enzymatic reactions. © 2013 Wiley Periodicals, Inc.