Quinoidal Azaacenes: 99 % Diradical Character.

ABSTRACT: Quinoidal azaacenes with almost pure diradical character (y=0.95 to y=0.99) were synthesized. All compounds exhibit paramagnetic behavior investigated by EPR and NMR spectroscopy, and SQUID measurements, revealing thermally populated triplet states with an extremely low-energy gap ΔE_ST' of 0.58 to 1.0 kcal mol^-1 . The species are persistent in solution (half-life≈14-21 h) and in the solid state they are stable for weeks.

SUBMITTER: Intorp SN 

PROVIDER: S-EPMC7384067 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature