2-Aryl substituted 3-oxophenalenoxyl radicals: π-Spin structures and properties evaluated by dimer structure

X-ray crystal structure analysis and variable temperature 1H NMR study have revealed the dimeric structure of 2-(p-methoxyphenyl)-3-oxophenalenoxyl neutral radical. Density functional theory calculations have shown that the kinetic instability of this radical is attributed to the relatively localized nature of the π-spin density distribution, which supports our previous ESR study.