https://doi.org/10.1007/PL00011089
On the theory of light scattering in molecular liquids
Institut für Physik, Johannes-Gutenberg Universität, 55099
Mainz, Germany
Corresponding authors: a latz@komath.physik.uni-mainz.de - b letz@komath.physik.uni-mainz.de
Received:
3
July
2000
Revised:
7
November
2000
Published online: 15 February 2001
The theory of light scattering for a system of linear molecules with
anisotropic polarizabilities is considered. As a starting point for
our theory, we express the result
of a scattering experiment in VV and VH symmetry as
dynamic correlation functions of tensorial
densities with l=0 and l=2. l, m denote indices
of spherical
harmonics. To account for all observed hydrodynamic singularities,
a generalization of the theory of Schilling and
Scheidsteger [1] for these correlation functions is
presented, which is capable to describe the light scattering
experiments from the liquid regime to the glassy state. As a
microscopic theory it fulfills all sum rules contrary to
previous phenomenological theories.
We emphasize the importance of the helicity index m for the
microscopic theory
by showing, that only the existence of m=1 components lead to the well
known Rytov dip in liquids and to the appearance of transversal sound
waves in VH symmetry in the deeply supercooled liquid and the
glass. Exact expressions for the phenomenological frequency
dependent rotation
translation coupling coefficients of previous theories are derived.
PACS: 64.70.Pf – Glass transitions / 78.35.+c – Brillouin and Rayleigh scattering; other light scattering / 64.70.Dv – Solid-liquid transitions / 61.25.Em – Molecular liquids
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001