MICROWAVE SPECTRUM, STRUCTURE, DIPOLE MOMENT, AND QUADRUPOLE COUPLING CONSTANTS OF 1,2,5-OXADIAZOLE,
Abstract
The microwave spectra of the normal species (C2H2N2O) and the (C(13)CH2N2O, C2H2N(15)NO, C2D2N2O, and C2HDN2O isotopic species of 1,2,5oxadiazole (furazan) were assigned. The value of the inertial defect indicates a planar structure for the molecule. The structural parameters obtained from the isotopic changes in the moments of inertia plus the center of mass condition are:O-N = 1.380 = 0.003 A, C=N = 1,300 = 0.003 A, C-C = 1.421 = 0.003 A, C-H = 1.076 = 0.003 A, NON = 110 degrees 24' = 20', <ONC = 105 deg. 49' = 20', <CCN = 108 deg. 59' = 20', <CCH = 130 deg. 10' = 35', <NCH = 120 deg. 51' = 35'. Stark effect measurements gave a dipole moment of 3.38 = 0.04 D. The nitrogen quadrupole coupling constants of the normal species were determined from an analysis of the hyperfine splittings of four low J Q-branch lines to be: chi-aa = -0.69 = 0.09 Mc./sec., chi-bb = -0.46 = 0.13 Mc./sec., chi-cc = 1.15 = 0.04 Mc./sec. These constants correctly predict the shape and splitting of an additional low J Rbranch line. The absence of a low lying vibrationally excited state, the absence of an out-of-plane component of the dipole moment, and the relative intensities of the quadrupole components of the lines of C2H2N2O and C2D2N2O are further evidence for the planarity and C-2v symmetry of the molecule. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1963
- Accession Number
- AD0612293
Entities
People
- A. P. Cox
- E. Saegebarth
Organizations
- Harvard University