The rotational spectra of five isotopologues of the molecular adduct 1,1,1-trifluoroacetonewater have been assigned using pulsed-jet Fourier-transform microwave spectroscopy. All rotational transitions appear as doublets, due to the internal rotation of the methyl group. Analysis of the tunneling splittings allows one to determine accurately the height of the 3-fold barrier to internal rotation of the methyl group and its orientation, leading to V3 = 3.29 kJ 3 mol1 and —(a,i) = 67.5, respectively. The water molecule is linked to the keton molecule on the side of the methyl group through a OH3 3 3O hydrogen bond and a CH3 3 3O intermolecular contact, lying in the effective plane of symmetry of the complex.
L.B.Favero, L.Evangelisti, A.Maris, A.Vega-Toribio, A.Lesarri, W.Caminati (2011). How Trifluoroacetone Interacts with Water. JOURNAL OF PHYSICAL CHEMISTRY. A, MOLECULES, SPECTROSCOPY, KINETICS, ENVIRONMENT, & GENERAL THEORY, 115, 9493-9497 [10.1021/jp112015r].
How Trifluoroacetone Interacts with Water
EVANGELISTI, LUCA;MARIS, ASSIMO;CAMINATI, WALTHER
2011
Abstract
The rotational spectra of five isotopologues of the molecular adduct 1,1,1-trifluoroacetonewater have been assigned using pulsed-jet Fourier-transform microwave spectroscopy. All rotational transitions appear as doublets, due to the internal rotation of the methyl group. Analysis of the tunneling splittings allows one to determine accurately the height of the 3-fold barrier to internal rotation of the methyl group and its orientation, leading to V3 = 3.29 kJ 3 mol1 and —(a,i) = 67.5, respectively. The water molecule is linked to the keton molecule on the side of the methyl group through a OH3 3 3O hydrogen bond and a CH3 3 3O intermolecular contact, lying in the effective plane of symmetry of the complex.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
