Higher-order interaction-induced effects on depolarized light scattering from fluids of optically anisotropic molecules

✍ Scribed by Branka M. Ladanyi

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 351 KB
• Volume: 121
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(85)87192-x

✦ Synopsis

The elk1 or higher-order lerms in dipole-induced dipole (DID) inleractions on the depolarized light scatlering inlensily in liquid oxygen is calculated using molecular dynamics cornpurer simulation. The rota1 induced dipole moment in lhe syslem is evaluated ileratively. Inclusion of multiple DID interaction depolatid imensily over the lirsl-order result ~crrns is found LO lead lo a non-negligible increase in Ihe I _ Introduction It is now well known that the interaction-induced part of the collective polarizability of dense fluids of optically anisotropic molecules contributes significantly to the depolarized light scattering (DLS) intensity [l-3]. In estimating this contribution to the intensity, only the leading term in the interaction between molecular induced dipoles is usually taken into account. The influence of this leading term often turns out to be quite substantial [4-71, so it is reasonable to expect that higher-order terms in this series might be important. Bancewicz derived an expression for the DLS intensity including all secondxwder DID terms and evaluated approximately the individual contributions [7]. He found that the contribution from the second-order interaction term in the collective polarizability, absent from earlier calculations, was nonnegligible and that it lead to a decrease in the intensity in the case of the two fluids of Lennard-Jones diatomics he considered. He used only pair distribution function information to obtain numerical estimates, and the accuracy of these calculations is thus somewhat uncertain. It is desirable to obtain a more accurate estimate of these higher-order terms.