Rovibrational Raman spectrum of dimethylacetylene

Abstract

The rovibrational Raman spectrum of dimethylacetylene (but-Zyne) was recorded photoelectrically at medium resolution. Depolarization ratios and relative normalized scattering cross-sections were determined for five fundamentals and a number of strong overtones.

Internal rotation, spin–orbit coupling, and low-frequency vibrations in the ground state of CH3–CC–CH+3and CD3–CC–CD+3

“…Excited vibrational levels of 2-butyne are well known from studies by high-resolution infrared [3][4][5] and Raman spectroscopy [2,6], so that the current understanding of the structure and dynamics in the electronic ground state of neutral 2-butyne can be regarded as excellent.…”

“…The properties of the ground state of 2-butyne have been intensively studied by high-resolution spectroscopy [2][3][4][5][6]. The nearly free internal rotation of the methyl groups around the axis defined by the linear chain of carbon atoms and the presence of six indistinguishable protons make it an ideal system to study large-amplitude motion in a molecular system with a high nuclear-permutation symmetry and develop the adequate group-theoretical tools [7][8][9][10][11][12][13].…”