Accession Number:

AD0645777

Title:

THE MICROWAVE SPECTRUM OF PIVALALDEHYDE,

Descriptive Note:

Corporate Author:

HARVARD UNIV CAMBRIDGE MASS DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

1966-07-14

Pagination or Media Count:

28.0

Abstract:

The microwave spectrum of pivalaldehyde CH33CCHO was investigated in the frequency region 9-40 kMcsec. The ground state, first and second excited states of the t-butyl torsion, and the first excited state of each of the three methyl torsions were assigned. The barrier to internal rotation of the t-butyl top was calculated from the splittings in the first excited state to be 1186 calmole, from the splittings in the second excited state to be 1176 calmole, and from the intensities of the first excited state relative to the ground state to be 1100 calmole. The excited states of the methyl torsions show no splittings, but the relative intensities yield barrier estimates of 2600 calmole, 3500 calmole, and 3800 calmole, if one assumes that the three tops are independent. On the basis of certain analogies with previously investigated molecules the lowest of these barriers is very tentatively assigned to a methyl group which is eclipsed with respect to the oxygen atom. The dipole moment components were computed from Stark effect measurements to be mu-a 2.56 D and mu-b 0.76 D. Author

Subject Categories:

  • Organic Chemistry
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE