G. Buntinx et al., TRANSIENT ABSORPTION AND RESONANCE RAMAN INVESTIGATION OF THE PHOTOCHEMICAL REACTIVITY OF 2,2'-BIPYRIMIDINE IN SOLUTION, Journal of physical chemistry, 99(8), 1995, pp. 2343-2352
The 248-nm photolysis products of 2,2'-bipyrimidine (22BPMY) and of it
s per-deuterated analogue in various organic solvents have been invest
igated by transient UV/visible absorption and time-resolved resonance
Raman spectroscopies in the nano/microsecond time scale. Reduction of
the lowest triplet state via electron abstraction from amines and via
hydrogen atom abstraction from hydrogen-donating solvents is evidenced
. The conformations of four transient species involved in the reactivi
ty, the tripler state, the anion radical, the H-adduct radical and its
protonated form, the dihydro cation radical, are discussed from the d
etailed analysis of the resonance Raman spectra. A very short-lived Ra
man spectrum detected on electron transfer is ascribed to an ion pair.
The existence of this ion pair is in agreement with the relative kine
tic behaviors of the different transient species involved in the react
ion.