THE S1 DYNAMICS OF 4- AND 5-METHYLPYRIMIDINE : THE ROLE OF FRAME AND INTERNAL ROTOR SYMMETRIES

摘要: Abstract The dynamics of the structural isomers 4-methylpyrimidine and 5-methylpyrimidine were studied with single rotorvibronic resolution after excitation vibronic bands S1 electronic state up to an excess energy ∼ 1000 cm−1. Quantum beats biexponential decays indicate intermediate case due coherent S1−T1 eigenstates. By comparing isomers, effects frame symmetry on density coupling T1 states their nonradiative ∑ S0 intersystem crossing decay rate are manifested. Despite expected effects, internal rotor A1 E show identical suggesting that torsional potentials in similar.