The rotational spectrum of cyclohexyl formate, chemically prepared within a supersonic expansion

The rotational spectra of the ground state and of one vibrational satellite of 2,3-benzofuran have been measured by millimetre-wave absorption free jet spectroscopy in the frequency range 60-78 GHz. The value of the inertial defect (-0.072 uÅ2) shows the molecule to be planar. The shifts of the rotational constants in going from the ground to the excited state indicate that the observed vibrational satellite does not belong to the two lowest energy motions, the butterfly and 1,3-ring-twisting, which undergo relaxation upon the supersonic expansion.

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The broadband rotational spectrum of fully deuterated acetaldehyde (CD3CDO) in a CW supersonic expansion

Journal of Molecular Spectroscopy ◽

10.1016/j.jms.2017.01.010 ◽

2017 ◽

Vol 342 ◽

pp. 17-24 ◽

Cited By ~ 7

Author(s):

Daniel P. Zaleski ◽

Chuanxi Duan ◽

Miguel Carvajal ◽

Isabelle Kleiner ◽

Kirill Prozument

Keyword(s):

Rotational Spectrum ◽

Supersonic Expansion

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From Molecular to Cluster Properties: Rotational Spectroscopy of 2-Aminopyridine and of Its Biomimetic Cluster with Water

Molecules ◽

10.3390/molecules26226870 ◽

2021 ◽

Vol 26 (22) ◽

pp. 6870

Author(s):

Adam Kraśnicki ◽

Zbigniew Kisiel ◽

Jean-Claude Guillemin

Keyword(s):

Hydrogen Bonds ◽

Room Temperature ◽

Rotational Spectroscopy ◽

Rotational Spectrum ◽

Base Pairs ◽

Supersonic Expansion ◽

Ring Molecules ◽

Isotopic Species ◽

Single Ring ◽

Cluster Properties

We report the observation and analysis of the rotational spectrum of a 1:1 cluster between 2-aminopyridine and water (AMW) carried out with supersonic expansion Fourier transform microwave spectroscopy at 4.7–16.5 GHz. Measurements of the 2-aminopyridine monomer (AMP) were also extended up to 333 GHz for the room-temperature rotational spectrum and to resolve hyperfine splitting resulting from the presence of two 14N quadrupolar nuclei. Supersonic expansion measurements for both AMP and AMW were also carried out for two synthesized isotopic species with single deuteration on the phenyl ring. Nuclear quadrupole hyperfine structure has also been resolved for AMW and the derived splitting constants were used as an aid in structural analysis. The structure of the AMW cluster was determined from the three sets of available rotational constants and the hydrogen bonding configuration is compared with those for clusters with water of similarly sized single-ring molecules. Experimental results aided by quantum chemistry computations allow the conclusion that the water molecule is unusually strongly bound by two hydrogen bonds, OH...N and O...HN, to the NCNH atomic chain of AMP with the potential to replace hydrogen bonds to the identical structural segment in cytosine and adenine in CT and AT nucleic acid base pairs.

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