Unstable intermediates. Part CLII. Radicals in thallous nitrate

Abstract

Exposure of thallous nitrate to ⁶⁰Co γ-rays at 77 K gave NO₃ radicals which exhibited strong charge-transfer interaction with two equivalent thallous ions and a weaker interaction with two others. Two well defined species were formed, one being lost preferentially on annealing above 77 K. These results are rationalised in terms of the crystal structure of the nitrate.

Exposure at room temperature gave NO₂ which again exhibited strong hyperfine interaction with four thallous ions, together with a second species, possibly also NO₂, but in a completely different environment, with one very strongly coupled thallous ion. The thallous hyperfine coupling was essentially isotropic, which indicates that the interaction stems from an electron donation from TI⁺ to the radical, which is the reverse of that normally associated with alkali-metal radical-anion systems.