Quinoidal Azaacenes: 99 % Diradical Character

Diradical character from the local spin analysis.

Diradical species are analyzed in light of the local spin analysis. The atomic and diatomic contributions to the overall 〈Ŝ(2)〉 value are used to detect the diradical character of a number of molecular species mostly in their singlet state, for which no spin density exists. A general procedure for the quantification of diradical character for both singlet and triplet states is achieved by using...

Structural fluctuation governed dynamic diradical character in pentacene.

We unravel intriguing dynamical diradical behavior governed by structural fluctuation in pentacene using ab initio molecular dynamics simulation. In contrast to static equilibrium configuration of pentacene with a closed-shell ground state without diradical character, due to structural fluctuation, some of its dynamical snapshot configurations exhibit an open-shell broken-symmetry singlet groun...

SUPPLEMENTARY INFORMATION Diradical character from the local spin analysis

Onset of diradical character in small nanosized graphene patches.

A family of small graphene patches, i.e., rectangular polyaromatic hydrocarbons (PAHs), that have both zigzag and armchair edges is investigated to establish their ground state electronic structure. Broken symmetry density functional theory (DFT) and plane wave DFT were used to characterize the onset of diradical character via relative energies of open-shell and closed-shell singlet states. The...

Twisted pyrene-fused azaacenes.

An approach for introducing twists in pyrene-fused azaacenes is reported. Depending on the volume and the rigidity of the silyl groups, different-sized twist angles, which oscillate between 4° and 24°, are induced along the longitudinal conjugated backbone.