Electron paramagnetic resonance study of the paramagnetic centers in gamma-irradiated 4-Nitrobenzaldehyde single crystal

Abstract

4-Nitrobenzaldehyde (C7H5NO3) (4NB) single crystals were obtained by slow evaporation technique. Single crystals were made paramagnetic by irradiation with a 60Co-gamma rays. Electron Paramagnetic Resonance (EPR) Spectroscopy method was used to detect the radiation damage center formed in the single crystals. As a result of temperature scanning of EPR spectra at different temperatures between 120 and 470 K, it was found to be independent of temperature. That's why the EPR study was done only at 300 K. The radiation effect caused the formation of the 4NB anion radical in the 4NB single crystal. All the protons in the structure created hyperfine structure splittings. The principal values of the hyperfine structure constants resulting from the interaction of the unpaired electron with protons, the principal values of the g-tensor and their direction cosines were calculated.