We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Research & business

View Profile

Publication details for Prof. Jan R.R. Verlet

Chatterley, A. S., Horke, D. A. & Verlet, J. R. R. (2012). On the intrinsic photophysics of indigo: a time-resolved photoelectron spectroscopy study of the indigo carmine dianion. Physical Chemistry Chemical Physics 14(46): 16155-16161.

Author(s) from Durham


The intrinsic photophysics of indigo has been studied using gas-phase time-resolved photoelectron imaging of the indigo carmine dianion (InC2−). The action spectrum reveals that the gas-phase absorption spectrum arising from the S1 ← S0 transition in InC2− has a similar solvent shift to that of neutral indigo. Femtosecond spectroscopy shows that the S1 state decays on a 1.4 ps timescale. Through isotopic substitution, the primary mechanism on the S1 excited state can be assigned to an intra-molecular proton transfer, which is the same as that which has been observed in solution. However, the excited state lifetime is significantly shorter in vacuum. These similarities and differences are discussed in terms of recent theoretical investigations of the S1 excited state of indigo.