Benchmark Computations of Nearly Degenerate Singlet and Triplet states of N-heterocyclic Chromophores : I. Wavefunction-based Methods

Shamik Chanda, Sangita Sen

In this paper we investigate the role of electron correlation in predicting the S${}_1$-S${}_0$ and T${}_1$-S${}_0$ excitation energies and hence, the singlet-triplet gap ($\Delta$E${}_{ST}$) in…