|
|
|
Schepin A.S. INDUCTION OF ELECTRONIC TRANSITIONS IN COLLISION COMPLEXES [O2-X], X = CO, NO, CO2, H2OSinglet oxygen — a general term used for the two metastable states (a, b) molecular oxygen (O2) with higher energy than the triplet state (X), which is the main. It has a very high oxidation activity when interacting with the organic substances involved in the biological processes of living organisms. Mechanisms of generation of singlet oxygen are explained by emerging within the oxygen molecule intense forbidden transitions: a-X, b-a, b-X systems bimolecular collision oksokompeksov. Currently, however, such systems are poorly understood. The method CASSCF / 6-311G ++ (2p, 2d) constructed section of the potential energy surface (PES) complex formation reactions [O2-X], X = CO, NO, CO2, H2O. Taking into account the spin-orbit coupling (SOC) calculated values of the moments of forbidden radiative transitions: M (aX), M (ba), M (bX), the Einstein coefficients A (transition probabilities) in the O2 molecule in the collision with the molecules of CO, NO, CO2 , H2O and the radiative lifetime of singlet oxygen in oxo complex bimolecular collision. According to the results of the work showed that the formation of bimolecular complexes [O2-X], where X = CO, NO, CO2, H2O removed spin prohibitions, whereby it becomes possible manifestation of illicit induced transitions in the oxygen molecule: singlet-singlet ba, characterized by high values compared to intensity molecule pure O2, and singlet-triplet aX, bX (defined only in the complex [O2-NO]). Also it found that the geometrical configuration of collisional oxo complexes are directly dependent on the values of the radiative lifetime, as well as the values of the moments induced forbidden transitions.Key words: collision complexes, the radiative lifetime, the excited state of oxygen stability of weakly bound complexes.
References:
1. Schweitzer, C. Physical mechanisms of generation and deactivation of singlet oxygen / C. Schweitzer, R. Schmidt // J. Chem. Rev. — 2003. — Vol. 103. — P. 1685–1757.
2. Kobzev, G.I. The dependence of the luminescence of molecular oxygen on the type and number of atoms that make up the complex, and the number of molecules of oxygen environment / G.I. Kobzev // Vestnik of OSU. — 2005. — № 1. — P. 150–156.
3. Rosenthal, I. Singlet O2 / I. Rosenthal, AA Frimer. — Vol. 1. Physical-Chemical Aspects. — Florida: CRC Press Inc., 1985. — Chapt. 2. — P. 13–38.
4. Minaev, B.F. Response calculations of electronic and vibrational transitions in molecular oxygen induced by interaction with noble gases / B.F. Minaev, G.I. Kobzev // Spectrochim. ActaPartA. — 2003. — Vol. 59. — P. 3387–3410.
5. Schepin, A.S. The lifetime of singlet oxygen in collision complexes of O2–C O2 / A.S. Schepin, S.A. Peshkov, T.V. Peshkov // Vestnik of OSU. — 2016. — № 3. — P. 92–97.
6. Shinkarenko, N.V. Singlet oxygen, methods for detection and / N.V. Shinkarenko, V.B. Aleskovsky // Russian Chemical. — 1981. — Vol. 50, Is. 3. — P. 406–428.
7. Urvaev, D.G. Role oksikomplekses of Se, Ga, and 3d–metals in the generation of singlet oxygen: dis. ... Cand. Chem. Science / D.G. Snatch. –Ufa: Bashkir.gos. University Press, 2015.
8. Granovsky, A.A. Firefly version 8.1.G [electronic resource] / A.A. Granovsky. — URL: www http://classic.chem.msu.su/gran/firefly/index.html.
9. Svishchev, I.M. Van der Waals Complexes of Water with Oxygen and Nitrogen: Infrared Spectra and Atmospheric Implications / I.M. Svishchev, R.J. Boyd // J. Phys. Chem. A. — 1998. — Vol. 102. — P. 7294–7296.
10. Kjaergaard, H.G. Complexes of Importance to the Absorption of Solar Radiation / H.G. Kjaergaard, T.W. Robinson, D.L. Howard // J. Phys. Chem. A. — 2003. — Vol. 107. — P. 10680–10686.
11. Kobzev, G.I. Effect of 5-methylresorcinol the spin conversion in the molecular oxygen / G.I. Kobzev // Journal of Structural Chemistry. — 2014. — Vol. 55, № 1. — P. 14–19.
12. Van der Waals and charge-transfer complexes of molecular oxygen and water / B.W. Byers et al. // Chem. Phys. Let. Vol. — 1992. — Vol. 192, № 2, 3. — P. 213–216.
13. Minaev, B.F. Collision-Induced Intensity of the b1Σg + –a1ΔgTransition in Molecular Oxygen: Model Calculations for the Collision Complex O2 + H2 / B.F. Minaev, S. Lunell, G.I. Kobzev // Intern. J. of Quant. Chem. — 1994. — V. 50. — P. 279–292.
14. Bregnhoj, M. Effect of Solvent on the O2 (a1Δg) → O2 (b1Σg +) Absorption Coefficient / M. Bregnhoj, P.R. Ogilby // J. Phys. Chem. A. — 2015. — Vol. 35, № 119. — P. 9236–9243.
15. Huber, K.P., Herzberg G. Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules / K.P. Huber, G. Herzberg // Van Nostrand. — New York, 1979. — P. 716.
About this article
Author: Shchepin A.S.
Year: 2016
|
|
Editor-in-chief |
Sergey Aleksandrovich MIROSHNIKOV |
|
|