Knowledge Bank

The quantum-chemical calculation by method MINDO/3 C1 for models of collision complex of oxygen molecule with chlorine atom had been performed. The intermolecular distance (R) is changed from 3,4 A to 2,8 A under the symmetrical geometry of rapprochement $(C2\nu )$ as well as under asymmetrical $(C8)$. It is shown, that under the asymmetrical rapprochement the intensity of transition $a\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Delta g-X3\Sigma g\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ in oxygen is enhanced into seven orders. In an isolated molecule $O2$ this transition is magnetic-dipole $(f=4\cdot 10-12)$ and induced by spin-orbit coupling (SOC); and in collision complex with chlorine it acquires electric-dipole character (without account of SOC) by some charge-transfer-state admixtures $O2\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}-Cl-$. It is interesting to not that the $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Delta g-X3\Sigma g\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ transition intensity in oxygen under the geometry of rapprochement $Ce(f=1,2\cdot 1-5)$ enhances in three orders the intensity of the same transition but under symmetrical configuration $C2v(f=7,4\cdot 10-8)$. Moreover the Radiative lifetime of oxygen molecule metastable state $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}\Delta g$ in the symmetry $C2v(\tau =0,68s)$ exceeds in 63 times the radiative lifetime than the $C8$ configuration.