Electron-loss centres from methylmercury hydride, dimethylcadmium and diethylcadmium: an EPR study

Abstract

Exposure of dilute solutions of methylmercury hydride in freon to ionizing radiation at 77 K generated two different radical cations. One, written as CH₃^. HgH⁺, has a large methyl proton hyperfine coupling with high spin density on the methyl ligand and the other (CH₃Hg^.H⁺) has a large coupling (460 G) to one proton, indicating a high spin density on the hydride ligand. In contrast, similar treatment of dimethyl- and diethyl-cadmium gave methyl and ethyl radicals directly at 77 K. These results are compared with those for various symmetrical R₂Hg compounds which give symmetrical radical cations with high spin density on mercury.