LIGHT SCATTERING BY LIQUIDS AND MOLECULAR SOLIDS
CALIFORNIA UNIV SANTA BARBARA DEPT OF PHYSICS
Pagination or Media Count:
Measurements of the frequency broadening caused by molecular rotations were made in liquid carbon disulfide and in liquid mixtures of carbon disulfide and carbon tetrachloride by observing scattered light from an Ar laser at 4880A. The spectral shape of the scattered light was found to be nearly Lorentzian. Half-widths of the scattered radiation in carbon disulfide range from about 0.1cm near the triple-point to 6cm near the boiling point. Addition of carbon tetrachloride to carbon disulfide at room temperature causes the half-widths to decrease. Measurements of the frequency broadening were used to calculate relaxation times for the attenuation of molecular rotations in liquids. Vibrational Raman scattering was excited in liquid and solid carbon monoxide and nitrogen, and orientation scattering was studied in liquid oxygen. Brillouin scattering measurements were made in room temperature liquids in which an Ar laser has been used as a source of excitation. A He3-Ne laser was used to excite Brillouin scattering in liquid NH3 and ND3. Measurements of the Brillouin shifts were used to calculate the velocity of sound of the phonons in the gigacycle frequency range. Velocity dispersions at about 2Gc in liquid NH3 and ND3 have been postulated to be due to a structural relaxation of the liquids.
- Atomic and Molecular Physics and Spectroscopy
- Nuclear Physics and Elementary Particle Physics