title: Conformationally resolved structures of jet-cooled acetaminophen by UV-UV hole-burning spectroscopy.
abstract: The conformational structures of jet-cooled acetaminophen were investigated in the gas phase by resonant 2-photon ionization and UV-UV hole-burning spectroscopy. In contrast to the results from a previous study, two nearly isoenergetic conformers were distinctly found in a supersonic molecular beam expansion and positively identified as the cis and trans isomers of acetaminophen by UV-UV hole-burning spectroscopy. The 0-0 bands of the cis and trans isomers were found at 33518.7 and 33485.6 cm(-1), respectively. The vibronic bands of the two isomers are close-lying and/or partially overlapping due to the small energy difference (33 cm(-1)) between the two 0-0 bands. As a consequence, the recorded resonant 2-photon ionization spectrum is highly congested in the low excitation energy region, which develops continuously into a featureless, broadened spectrum in the high energy region.
authors.affiliation: Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University, Jinju , Republic of Korea.
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Lee
authors.forename: Ahreum
authors.initials: A
authors.lastname: Min
authors.forename: Yusic
authors.initials: Y
authors.lastname: Kim
authors.forename: Ahreum
authors.initials: A
authors.lastname: Ahn
authors.forename: Jinyoung
authors.initials: J
authors.lastname: Chang
authors.forename: Sang Hak
authors.initials: SH
authors.lastname: Lee
authors.forename: Myong Yong
authors.initials: MY
authors.lastname: Choi
authors.forename: Seong Keun
authors.initials: SK
authors.lastname: Kim
mesh_terms: D000082:Acetaminophen / Q000737:chemistry*; D008968:Molecular Conformation; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000082:Acetaminophen