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 000 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.