M. Negrerie et al., PHOTOIONIZATION AND DYNAMIC SOLVATION OF THE EXCITED-STATES OF 7-AZAINDOLE, Journal of physical chemistry, 97(19), 1993, pp. 5046-5049
The excited-state photophysics of the biological probe, 7-azaindole, a
re examined in water and methanol. Electrons in a presolvated state ab
sorbing in the infrared appear within the excitation pulse width of 13
0 fs. 330 +/- 100 fs is required for the presolvated electron to achie
ve the spectrum characteristic of the completely solvated electron. An
excited-state transient absorbance decays in approximately 350 fs for
7-azaindole and its methylated analog, N1-methyl-7-azaindole(1M7AI),i
n the region 400-450 nm in water and methanol. The instantaneous appea
rance of the electron in the infrared is attributed to the decay of th
e 1L(b) excited-state that overlaps the 1L(a) excited state of 7-azain
dole. The rapid decay of the excited-state transient absorbance is att
ributed to preferential, dynamic solvation of the 1L(a) state. 7-Azain
dole thus provides an interesting example of a molecule whose excited
state is continuously and dynamically solvated but which also produces
a species, e(aq)-, whose solvation appears to occur in a stepwise pro
cess.