Studies of structural isomers o-, m-, and p-fluorophenylacetylene by two-color resonant two-photon mass-analyzed threshold ionization spectroscopy.
We report the vibrational spectra of o-fluorophenylacetylene (OFPA), m-fluorophenylacetylene (MFPA), and p-fluorophenylacetylene (PFPA) in the electronically excited S1 and cationic ground D0 states. These new data show that the relative location of the fluorine atom with respect to the acetylenic group can influence the transition energy and molecular vibration. The adiabatic ionization energies of these structural isomers follow the order: PFPA < OFPA < MFPA. It is found that the molecular geometries of these molecules in the D0 state resemble those in the S1 state. Detailed spectral analysis suggests that the in-plane ring deformation vibrations are slightly "harder" in the D0 state than the corresponding ones in the S1 state.
Institute of Atomic and Molecular Sciences, Academia Sinica , P.O. Box 23-166, 1 Section 4, Roosevelt Road, Taipei 10617, Taiwan.
Vidya S
VS
Shivatare
Aniket
A
Kundu
G Naresh
GN
Patwari
Wen Bih
WB
Tzeng