Triplet state formation and quenching dynamics of 2-mercaptobenzothiazole in solution

Abstract

An adduct-mediated triplet energy transfer from a triplet thione to an alkene is observed with time-resolved vibrational absorption spectroscopy.

Intermolecular Hydrogen Bonding Controlled Intersystem Crossing Rates of Benzophenone

“…It is at first sight surprising that the T 2 → T 1 IC, which occurs with a time constant of ∼11 ps, is slower by an order of magnitude than the ISC rate. However, similar time scales have been reported for IC between the triplet states of various aromatic ketones − and attributed to either thermal , or kinetic equilibrium. For Bzp in solution, we propose that the IC rate will be dictated by the vibrational energy transfer (VET) rate to the solvent, which quenches the rapid exchange between the T 2 and T 1 states by relaxation to the minimum on the T 1 state.…”

Femtosecond to microsecond observation of the photochemical reaction of 1,2-di(quinolin-2-yl)disulfide with methyl methacrylate

“…This procedure gave good agreement between experimental and calculated infrared frequencies for the compounds of interest in this study. 9,39 Calculations of absorption spectra of the carbon centered addition radical (denoted as QS-MMA for the reaction with MMA) used time-dependent density functional theory (TDDFT) with the 6-311++G(3df,3pd) basis set. Enthalpies of activation for addition reactions of the various aromatic thiyl radical with styrene illustrated in Figure 1 were calculated using the CAM-B3LYP density functional, 40 with the 6-311++G(d,p) basis set, because reliable transition states for the addition reaction could not be obtained with the B3LYP method.…”

Mapping the multi-step mechanism of a photoredox catalyzed atom-transfer radical polymerization reaction by direct observation of the reactive intermediates

“…In this way, reaction pathways may be observed on timescales from hundreds of femtoseconds up to tens of milliseconds. [29][30][31] The resulting advantage is dynamic real-time tracking of short-and longer-lived intermediates, typically spanning picosecond to microsecond lifetimes, allowing iden-tication and kinetic analyses for species impossible to observe with steady state techniques.…”