Mass analyzed threshold ionization spectra of phenol⋯Ar₂: ionization energy and cation intermolecular vibrational frequencies

Abstract

The phenol + Á Á ÁAr 2 complex has been characterized in a supersonic jet by mass analyzed threshold ionization (MATI) spectroscopy via different intermediate intermolecular vibrational states of the first electronically excited state (S 1 ). From the spectra recorded via the S 1 0 0 origin and the S 1 b x intermolecular vibrational state, the ionization energy (IE) has been determined as 68 288 AE 5 cm À1 , displaying a red shift of 340 cm À1 from the IE of the phenol + monomer. Well-resolved, nearly harmonic vibrational progressions with a fundamental frequency of 10 cm À1 have been observed in the ion ground state (D 0 ) and assigned to the symmetric van der Waals (vdW) bending mode, b x , along the x axis containing the C-O bond. MATI spectra recorded via the S 1 state involving other higher-lying intermolecular vibrational states (s 1 s , b 3 x , s 1 s b 1 x , s 1 s b 2 x ) are characterized by unresolved broad structures.

Rotamers of m-chloroanisole studied by two-color resonant two-photon mass-analyzed threshold ionization spectroscopy

“…These methods can provide information about the active vibrations of rotamers in the electronically excited state. If the zero-kinetic energy (ZEKE) photoelectron [16][17][18] or mass-analyzed threshold ionization (MATI) [19][20][21][22][23] method couples with the resonant excitation scheme, it can provide information about the precise adiabatic IEs and active cation vibrations of the selected rotamers. Particularly, the MATI method has mass information and is suitable for studies of radicals, complexes, clusters, and isotopologues.…”

Structures and IR/UV spectra of neutral and ionic phenol–Arn cluster isomers (n≤ 4): competition between hydrogen bonding and stacking

“…6,32,37,41,46,47,50,62 REMPI of neutral (10) generates (10) in the cationic state, which can subsequently isomerise toward the more stable (H00) isomer on the ps timescale (as was shown for PhOH + -Kr) 50 and dissociate into PhOH + + Ar at the ionisation excess energy of E exc = 535 AE 3 cm À1 . 47 REMPI of neutral (11) produces (11) in the D 0 state, which undergoes isomerisation toward the more stable (H10) or (11) H isomers with a time constant of 7 ps.…”

Two-dimensional laser induced fluorescence spectroscopy of van der Waals complexes: Fluorobenzene-Arn (n = 1,2)

“…Their Raman technique is primarily sensitive to the intermolecular bend modes involving libration of the aromatic. Phenol-Ar 2 provides a recent example where the S 1 vibrational structure of an aromatic-Rg2 trimer has been observed, 42 although in that case it was a precursor to a more detailed study of the intermolecular modes of the corresponding cation.…”