ESR of Gamma Irradiated C₂H₂0₄.2H₂O Single Crystal

Improving sensitivity and resolution in solid-state nuclear magnetic resonance

“…Many of the γ-irradiated samples shown here have been previously studied by EPR spectroscopy, with a summary of the proposed radicals species summarized in the Supplemental Information (Figure S1). [89][90][91][92][93][94][95][96][97][98][99][100][101] γ-irradiated glucose is proposed to have two stable carbon-centered radicals, denoted RI-A and RII-C. γ-and X-ray irradiation of histidine hydrochloride monohydrate was proposed to lead to formation of a carbon-centered radical via deamination. 92 Malic acid is known to lose a hydroxide during γ-irradiation.…”

“…94 Maleic acid is proposed to form a radical of the form HOOC-H2C-•CH-COOH during irradiation at room temperature, 90 although carboxyl and vinyl radicals are seen to form when irradiated by either γ-or X-rays at 77 K. 91 γ-irradiated oxalic acid dihydrate forms the oxalate biradical, and the hyperfine splittings come from the waters of hydration. 93,101 While no study was found for studying the impact of γ-, electron beam, or X-ray irradiation on salicylic acid, it is known to create small amounts of radicals when exposed to either heat 100 or UV light. 99 Four different radicals were proposed for formation under γ-irradiation for sulfathiazole, although there is no strong evidence for any of them.…”