We report a combined experimental and computational study of carbon dioxide activation at gas-phase Ho+ and HoO+ centres. Infrared action spectra of Ho(CO2)n+ and [HoO(CO2)n]+ ion-molecule complexes have been recorded...

Femtosecond pump-probe photoelectron spectroscopy measurements using an extreme ultravioletprobe have been made on the photodissociation dynamics of UV (269 nm) excited CH3I. TheUV excitation leads to population of the 3Q0...

Methyl cinnamate (MC) is an ester within the cinnamate family. Recent time-resolved gas-phase studies have suggested that upon excitation to its first singlet ππ* (1 1 ππ*) state, there is initial decay to the lowest lying singlet 1 nπ* (1 1 nπ*) state within 10 ps, en route to trans-cis isomerisation. In the present study, we have implemented time-resolved ion yield (TR-IY) and time-resolved photoelectron spectroscopy (TR-PES) experiments in the gas-phase to precisely determine the lifetime of the 1 1 ππ* state. We found this lifetime to be ∼ 4.5 ps using both TR-IY and TR-PES. MC was also studied in a more complex cyclohexane solution environment, using transient electronic absorption spectroscopy. Along with complementary steady-state irradiation and 1 H NMR studies, these studies demonstrate that trans-cis isomerisation is preserved in the more complex, cyclohexane solution environment.

We present a combined experimental and quantum chemical study of gas-phase group 9 metal nitrosyl complexes, M(NO) n + (M = Co, Rh, Ir). Experimental infrared photodissociation spectra of mass-selected ion-molecule complexes are presented in the region 1600 cm–1 to 2000 cm–1 which includes the NO stretch. These are interpreted by comparison with the simulated spectra of energetically low-lying structures calculated using density functional theory. A mix of linear and nonlinear ligand binding is observed, often within the same complex, and clear evidence of coordination shell closing is observed at n = 4 for Co(NO) n + and Ir(NO) n +. Calculations of Rh(NO) n + complexes suggest additional low-lying five-coordinate structures. In all cases, once a second coordination shell is occupied, new spectral features appear which are assigned to (NO)2 dimer moieties. Further evidence of such motifs comes from differences in the spectra recorded in the dissociation channels corresponding to single and double ligand loss.