Electron spin resonance study of x-irradiated single crystals of dimethyl sulfone

Journal Article · Wed Jun 15 00:00:00 EDT 1977 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.433882· OSTI ID:7292944

Andersen, R S

The ESR spectra of x-irradiated single crystals of dimethyl sulfone, O/sub 2/S(CH/sub 3/)/sub 2/ have been examined at temperatures from 77 to 353 K. Between 77--153 K the spectra are dominated by an isotropic quartet of lines of intensity ratio 1:3:3:1, centered at g=2.0026 +- 0.0001, with a hyperfine interval of 20.9 +- 0.2 G. This spectrum originates from a methyl radical formed by the breaking of an S--C bond. On warming, the intensity of the methyl quartet decreased markedly at 163 K, being replaced by a singlet signal after several irreversible radical conversions had taken place. This singlet, which was stable from 173 to 333 K, is characterized by g values 2.0022, 2.0061, and 2.0067 +- 0.0001. No hyperfine structure was observed. This spectrum is attributed to the O/sub 2/SCH/sub 3/ radical. The g=2.0022 is oriented perpendicular to the --SO/sub 2/ plane, as expected for an unpaired electron principally located in a 3p (..pi..) orbital on the S atom. The other g values are symmetrically located with respect to the two S--O bonds and lie on the SO/sub 2/ plane. This indicates that the remaining S--C bond, on warming, reorients itself into the SO/sub 2/ plane. Observation of the /sup 33/S spectrum confirms this interpretation. Spin densities of the unpaired electron on the S atom are rho/sub 3//sub s/=0.074 and rho/sub 3//sub p/=0.33.

• Research Organization: Department of Physics, Clark University, Worcester, Massachusetts 01610
• OSTI ID: 7292944
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 66:12; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
CRYSTALS
DECOMPOSITION
ELECTROMAGNETIC RADIATION
ELECTRON SPIN RESONANCE
IONIZING RADIATIONS
MAGNETIC RESONANCE
MONOCRYSTALS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADICALS
RADIOLYSIS
RESONANCE
SULFONES
X RADIATION