| Autor: |
Hansen, Anne S., Huchmala, Rachel M., Vogt, Emil, Boyer, Mark A., Bhagde, Trisha, Vansco, Michael F., Jensen, Casper V., Kjærsgaard, Alexander, Kjaergaard, Henrik G., McCoy, Anne B., Lester, Marsha I. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 4/28/2021, Vol. 154 Issue 16, p1-9, 9p |
| Abstrakt: |
The infrared (IR) spectrum of tert-butyl hydroperoxide (TBHP) in the region of the first OH-stretching overtone has been observed under jet-cooled and thermal (300 K, 3 Torr) conditions at ∼7017 cm−1. The jet-cooled spectrum is recorded by IR multiphoton excitation with UV laser-induced fluorescence detection of OH radical products, while direct IR absorption is utilized under thermal conditions. Prior spectroscopic studies of TBHP and other hydroperoxides have shown that the OH-stretch and XOOH (X = H or C) torsion vibrations are strongly coupled, resulting in a double well potential associated with the torsional motion about the OO bond that is different for each of the OH-stretching vibrational states. A low barrier between the wells on the torsional potential results in tunneling split energy levels, which leads to four distinct transitions associated with excitation of the coupled OH-stretch-torsion states. In order to interpret the experimental results, two theoretical models are used that include the OH-stretch-torsion coupling in TBHP. Both methods are utilized to compute the vibrational transitions associated with the coupled OH-stretch-torsion states of TBHP, revealing the underlying transitions that compose the experimentally observed features. A comparison between theory and experiment illustrates the necessity for treatments that include OH-stretch and COOH torsion in order to unravel the spectral features observed in the first OH-stretching overtone region of TBHP. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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