Radiation-induced defects in sucrose single crystals, revisited: a combined electron magnetic resonance and density functional theory study.

Department of Solid State Sciences, Ghent University, Krijgslaan 281-S1, B-9000 Gent, Belgium.
Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy (Impact Factor: 1.98). 06/2008; 69(5):1372-83. DOI: 10.1016/j.saa.2007.09.033
Source: PubMed

ABSTRACT The results are presented of an electron magnetic resonance analysis at 110 K of radiation-induced defects in sucrose single crystals X-irradiated at room temperature, yielding a total of nine (1)H hyperfine coupling tensors assigned to three different radical species. Comparisons are made with results previously reported in the literature. By means of electron paramagnetic resonance and electron nuclear double resonance temperature variation scans, most of the discrepancies between the present 110 K study and a previous 295 K study by Sagstuen and co-workers are shown to originate from the temperature dependence of proton relaxation times and hyperfine coupling constants. Finally, radical models previously suggested in the literature are convincingly refuted by means of quantum chemical density functional theory calculations.

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