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Updated: Jul 16, 2026

Molecular Beam Mass Spectrometry With Tunable Vacuum Ultraviolet (VUV) Synchrotron Radiation
Published on: October 30, 2012
Infrared laser spectroscopy of uracil and thymine in helium nanodroplets: vibrational transition moment angle study
Myong Yong Choi1, Roger E Miller
1Department of Chemistry, The University of North Carolina at Chapel Hill, North Carolina 27599, USA. mychoi@gnu.ac.kr
Abstract:
Vibrational spectra are reported in the N-H stretching region for uracil and thymine monomers in helium nanodroplets. Each monomer shows only a single isomer, the global minimum, in agreement with previous experimental and theoretical studies. The assignment of the infrared vibrational bands in the spectra is aided by the measurement of the corresponding vibrational transition moment angles (VTMAs) and ab initio frequency calculations. The ambiguity in the VTMA assignment of the N3H band for the uracil monomer is explained by the presence of dimer bands, which are overlapped with the monomer band.
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