Identification of isotopomers in natural abundance using two dimensional laser induced fluorescence: S1–S0 spectral shifts for the four 13C isotopomers of fluorobenzene

The spectral shifts associated with the S1–S0 0 0 0 transition for the four 13C isotopomers of fluorobenzene have been determined using two dimensional laser induced fluorescence (2D-LIF), demonstrating this to be a powerful tool for separating overlapped spectral features associated with molecular species of the same mass. The 13C isotopomers were assigned with the aid of ab initio calculations of the magnitude of the vibrational frequency changes on 13C substitution. The 2D-LIF technique is expected to be useful for separating overlapped spectra from species such as configurational isomers, where mass-based spectroscopic techniques can have difficulty.