Abstract
The structure of a radical in gamma-irradiated Rochelle salt, which was named center No. 1 by Moulton and Moulton was studied by the electron spin resonance spectra at X-band frequency. The principal values of hyperfine tensors for the two protons were determined to be 5.4, -0.0, and -0.9 gauss, and 4.8, 3.4, and -4.0 gauss. The principal values of g -tensor was also determined to be 2.0049, 2.0039, and 2.0024. Form the informations obtained from the hyperfine coupling tensors and g -tensor, the structure of center No. 1 was proposed to be OOC\(\dot{\text{C}}\)(OH)CH·(OH)COO which was formed by the breaking of C-H bond in the tartrate molecule. It is identical with the one of center No. 3 in the chemical composition, but different in the geometrical structure.