Early Events in the Nonadiabatic Relaxation Dynamics of 4‑(N,N‑Dimethylamino)benzonitrile

摘要: 4-(N,N-Dimethylamino)benzonitrile (DMABN) is the archetypal system for dual fluorescence. Several past studies, both experimental and theoretical, have examined mechanism of its relaxation in gas phase following photoexcitation to S2 state, without converging a single description. In this contribution, we report first-principles simulations early events involved process performed using nonadiabatic trajectory surface hopping (TSH) approach combination with ADC(2) electronic structure method. verified reproduce ground- excited-state structures DMABN reasonably close agreement previous theoretical benchmarks. The TSH predict that internal conversion from state S1 takes place as 8.5 fs, on average, after initial photoexcitation, no significant torsion dimethylamino group relative aromatic ring. As evidenced by supporting EOM-CCSD calculations, population transfer ...