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Published on: April 1, 2013
Two Conformers of N,N-Diethylpropionamide As Observed by Microwave Spectroscopy and Quantum Chemistry
Raphaela Kannengießer1, Wolfgang Stahl1, Ha Vinh Lam Nguyen2
1Institute of Physical Chemistry, RWTH Aachen University , Landoltweg 2, D-52074 Aachen, Germany.
Abstract:
The microwave spectra of two conformers of N,N-diethylpropionamide were recorded using a molecular beam Fourier transform microwave spectrometer operating in the frequency range 2-26.5 GHz. Hyperfine splittings arising from the (14)N quadrupole coupling effect were observed and analyzed. Fits using a rigid rotor model with centrifugal distortion correction and first-order perturbation approach for the quadrupole coupling yielded highly accurate molecular parameters and standard deviations within the measurement accuracy for both conformers. Complementary quantum chemical calculations were carried out for a conformational analysis, theoretical values of the spectroscopic constants, and the (14)N nuclear quadrupole coupling constants.
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