Spectroscopic Characterization of Structural Isomers of Naphthalene: 1-Phenyl-1-butyn-3-ene
Joshua Sebree, David F. Plusquellic, Timothy Zwier
With the growing interest in the role naphthalene may play in planetary atmospheres and the interstellar medium, it is important to characterize other C10H8 structural isomers. These C10H8 isomers, once formed, may undergo an isomerization reaction to form naphthalene, or react via alternative pathways that lead away from its formation. The laser induced fluorescence (LIF) and single vibronic level dispersed fluorescence (DFL) spectra have been collected for the S0-S1 transition of the C10H8 isomer 1-phenyl-1-butyn-3-ene. The S0-S1 origin of PAV at 34922 cm-1 is very weak, with vibronic bands located 464.0 and 530.5 cm-1 above the origin dominating the LIF spectrum, giving evidence for strong vibronic coupling in the excited state. The DFL spectra for several vibronic bands in the LIF have been collected. Vibrational assignments were made with assistance from ab initio calculations. Unlike its close structural isomer 1-phenyl-1-buten-3-yne, PAV shows no evidence for a fast non-radiative process within the first 1400 cm-1 above the S1 origin.