ESR Line Shapes in Glasses of Copper Complexes

The study by Sands of ESR line shapes of polycrystalline copper complexes has been extended and various ``anomalies'' discovered in the line shapes. The spectrum of copper phthalocyanine dissolved in concentrated H2SO4 has been studied at 77°K. The M=−32 hyperfine line has a behavior very different from that discussed by Sands. Isotropic extra hyperfine structure, arising from the presence of the ligand nitrogens, is easily discernible even in the glass.