Accession Number:

AD0612475

Title:

ROTATIONAL ISOMERISM AND MICROWAVE SPECTROSCOPY. III. THE MICROWAVE SPECTRUM OF 3-FLUOROPROPENE,

Descriptive Note:

Corporate Author:

HARVARD UNIV CAMBRIDGE MASS MALLINCKRODT LAB

Personal Author(s):

• Hirota,Eizi

Report Date:

1964-01-01

Pagination or Media Count:

64.0

Abstract:

The 3-fluoropropene molecule has been confirmed by microwave spectroscopy to exist in two rotational isomers, cis and gauche. Rotational constants in the ground vibrational state were determined. Rotational transitions are also assigned for isotopic species, eight of the cis and nine of the gauche form. By using Costains method the molecular structure was determined separately for the two isomers. The dipole moment and its components along the principal axes of inertia were also found. Through the temperature dependence of the intensity ratio the cis form is found more stable than the gauche form by 166 67 calmole. The energies of the first and the second excited states of the C-C torsion were determined by the relative intensity measurement. Some of the spectra in the excited states of the gauche form are doublets due to the tunnel effect through the trans barrier. Using these data a potential function for the rotation around the C-C single bond is drawn. A correlation is pointed out between the potential function and the binding states of carbon atoms forming the rotation axis. Author

Descriptors:

• *MOLECULAR ISOMERISM
• MICROWAVE SPECTROSCOPY
• ALKENES
• FLUORIDES
• MOLECULAR ROTATION
• STEREOCHEMISTRY
• BAND SPECTRA
• ATOMIC ENERGY LEVELS
• CHEMICAL BONDS
• LABELED SUBSTANCES
• DIPOLE MOMENTS
• STABILITY
• THERMOCHEMISTRY

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE