Showing papers on "DPPH published in 1983"

TL;DR: In this paper, susceptibility and ESR measurements are performed on single crystals of solvent-free 2,2-diphenyl-l-picrylhydrazyl (DPPH) between 1.5 and 300 K. The susceptibility measurements are explained by a pair model but 4% nonpairing paramagnetic centres are observed at low temperatures.