Gas and solution phase chloroiodomethane short-time photodissociation dynamics in the B-band absorption

Resonance Raman spectra were obtained within and to the red of the B-band absorption spectrum of gas phase chloroiodomethane and chloroiodomethane in cyclohexane solvent. The spectra show the fundamental and overtones of the nominal CI stretch (nν5) and combination bands of the CH2 wag (ν3), ICCl bend (ν6), and the CH2 scissor (ν2) fundamentals with the CI stretch bands (nν5). The chloroiodomethane B-band short-time photodissociation dynamics have significant substituent effects relative to the B-band of iodomethane due to the presence of the CCl chromophore n(X) → σ∗ (CX) transitions ≈170 nm that are close to the B-band absorption of chloroiodomethane but absent in iodomethane.