We are studying
the electronic structure of small halogen-containing radicals
(CH2Cl, CH2F, etc.) that are involved into the
ozone depletion process in collaboration with the
experimental group of
Prof. Hanna Reisler (USC).
Among interesting findings are additional bonding due to the
interaction of the unpaired electron with the lone pair of halogens,
and unusually large (i. e., ~100%) negative
anharmonicities of out-of-plane vibrational modes.
Ground state: bond order = 3/2
(full σ + 1/2π).
CCl bond contraction, frequency
increase, and anomalous charge distribution:
Valence 12A1 state: bond order
= 3/2 (1/2σ + full π).
CCl bond elongation and OPLA frequency increase.
Rydberg states: bond order = 2
(full σ + full π).
CCl bond contraction and OPLA frequency increase.
Effective potentials for OPLA motions in CH2Cl and
CH2F calculated at the CCSD(T)/6-311(+,+)G(3df,3pd) level
of theory. Note that the fundamental 0-1 transition differs by more
than factor of two from the harmonic frequency.
30. S. V. Levchenko, A. V. Demyanenko, V. L. Dribinski, A. B. Potter, H. Reisler, and A. I. Krylov
Rydberg-valence interactions in CH2Cl→CH2+Cl
photodissociation: Dependence of absorption probability on ground
state vibrational excitation
J. Chem. Phys. 118, 9233 – 9240
PDF (119 kB)
25. S. V. Levchenko and A. I. Krylov
Electronic structure of halogen-substituted methyl radicals: Equilibrium geometries and vibrational spectra of CH2Cl and CH2F
J. Phys. Chem. A 106, 5169 – 5176
PDF (86 kB)
21. S. V. Levchenko and A. I. Krylov
Electronic structure of halogen-substituted methyl radicals: Excited
states of CH2Cl and CH2F
J. Chem. Phys. 115, 7485 – 7494
PDF (133 kB)