Effect of the vibrational excitation on the non-radiative deactivation rate of the S1 state of p-cresol(NH3) complex

Effect of the intermolecular hydrogen bond conformation on the structure and reactivity of the p-cresol(H2O)(NH3) van der Waals complex

“…The effect of CH 3 substitution on this process shows contradictory results. While the photodissociation dynamics of bare PhOH 2 and p-CrOH 3 are very similar, the lifetime of the S 1 state of the p-CrOH(NH 3 ) complex decreases monotonically upon vibrational excitation, 13 at variance with the results for PhOH(NH 3 ) for which vibrational-mode specificity was reported. 11 This effect was assigned to the enhancement of the rates of intracluster vibrational energy redistribution (ICVR) as a consequence of coupling between the low frequency modes associated with the CH 3 group in p-CrOH with the otherwise relatively isolated intermolecular modes.…”

“…Hydrogen bonds of the type OH-N, NH-O, OH-O and OH-S are important in many chemical and biological processes, making the excited state dynamics of hydrogen bonded complexes of PhOH or p-CrOH with H 2 O, 5-8 NH 3 [9][10][11][12][13] and H 2 S 8 the subject of many studies in the last decade, especially since the discovery of excited state hydrogen atom transfer (ESHT) in PhOH(NH 3 ) n complexes: 10,12 PhOH*(NH 3 ) n -PhO + NH 4 (NH 3 ) nÀ1…”

New determination of the adiabatic ionization potential of the BaOH radical from laser photoionization-molecular beam experiments and ab initio calculations

“…The ensuing molecular beam, which contained BaOH products of the reaction between water and electronically excited Ba atoms, was collimated with a 4.0 mm diameter skimmer that was placed 6 cm downstream from the nozzle, before entering the ionization region of a differentially pumped, homemade Wiley-McLaren time-of-flight mass spectrometer (TOF-MS) with a mass resolution of m/ m = 355. 24 The BaOH radicals were photoionized under single-photon ionization conditions at a total distance of 23 cm from the nozzle by either using a frequency-doubled dye laser (Lumonics HD500, 0.04 cm −1 bandwidth), operating on Rhodamines (R-610, R-590, and R-575, Exciton) and pumped by a Nd:YAG laser (Spectra-Physics INDI 40-10, 10 ns FWHM) at 532 nm, or the fourth harmonic (266 nm) of the latter. Photoions were detected on microchannel plates after mass separation through the TOF-MS (46 cm flight length).…”

REMPI and IR-UV double resonance spectroscopy of 3-aminophenol·(NH3)1 cluster in the gas phase

“…Fluorophenols were studied to reveal that ESHT is faster in o-fluorophenol than in m-or p-fluorophenol, due to the mixing of the initially excited pp* and the dissociating pr* state through out-of-plane vibration [8]. The effect of methyl substitution was studied with a p-cresolÁ(NH 3 ) 1 complex, which showed no vibrational-mode specificity as a result of the mixing of intermolecular vibrations with those of the methyl group [9].…”