Rayleigh ratio depolarized

M.P. Bogaard, A.D. Buckingham, R.K. Pierens, A.N. White, Rayleigh scattering depolarization ratio and molecular polarizability anisotropy for gases. J. Chem. Soc. Faraday Trans. 74(12), 3008-3015 (1978)... 

Certain general relations used with the static scattering in the ROD limit from isotropic solutions in the absence of depolarized scattering (R J,q,c)=Q)) are gathered in this section, hi these limits, for a monodispersed solute, the Rayleigh ratio may be expressed in the form [4, 5,10,11,13,24,49, 58]... 

Kaye W, McDaniel JB (1974) Low-angle laser light scattering - Rayleigh factors and depolarization ratios Appl Opt 13 1934-1937... 

G. C. Gray and H. I. Ralph. Virial expansion for the depolarization ratio of Rayleigh scattering from monatomic gases. Phys. Lett. A, 33 165-166 (1970). 

The Gas Phase Polarizability Anisotropy. Murphy50 has measured the depolarization ratio for Rayleigh scattering, pR, and analysed the intensity distribution in the rotational Raman spectrum of the vapour at 514.5 nm. The ratio R20 of the invariants of the a,-,aA/ tensor can be determined by fitting the rotational Raman distribution, and a is known (from the Zeiss-Meath formula). Knowledge of the three quantities, a, pR and R2o, allows the polarizability anisotropy, Aa, and the three principal values of the tensor to be calculated. The polarizability anisotropy invariant is numerically equal to the quantity,... 

Figure 2. Experimental depolarization ratio r](,p(v) — /(/ v) /// (v) of the binary Rayleigh band of gaseous CF4 ( + ) at 294.5 K. The depolarization ratio for the V Raman band is also...

This behavior is illustrated in Fig. 6. Because of the assumed weak dependence of Pg on Q, the i = 0 band governed by the constant term p° , strongly dominates the Rayleigh excitation profile. The fundamental REP, however, shows the predicted doublet of resonances corresponding to y = 0 and v = 1 with a depolarization ratio pi that peaks halfway between the bands. In the following we shall call this pattern a Mortensen doublet. The overtones in Fig. 6 are much weaker (by a factor of lO or more) than... 

By combining classical samplings with quantum chemistry semiempirical TDHF calculations the impact of dynamic fluctuations on the first hyperpolarizability of helical strands has been evidenced . In particular, these fluctuations are responsible for relative variations of 20% in the hyper-Rayleigh responses in both pyridine-pyrimidine (py-pym) and hydrazone-pyrimidine (hy-pym) strands. Dynamical disorder has an even more important impact on the electric field-induced second harmonic generation responses, whose variations can reach 2 (py-pym) or 5 (hy-pym) times their mean value. These results demonstrate that geometrical fluctuations have to be taken into account for a reliable description of the second-order NLO properties in flexible structures such as helical strands. This work has also highlighted the relationships between the nature of the unit cell and the helical conformation of foldamers and their second-order NLO responses. In particular, the value of the hyper-Rayleigh depolarization ratio, which is characteristics of octupolar symmetry, is related to the helix periodicity, of three unit cells per turn in both compounds. 

M. Monan, J.-L. Bribes, R. Gauftes, Measurement of weak depolarization ratios of the Rayleigh scattering of gases using Raman spectroscopy. J. Raman Spectroscopy 12(2), 190-... 

W.F. Murphy, The Rayleigh depolarization ratio and rotational Raman spectium of water vapor and the polarizability components for the water molecule. J. Chem. Phys. 67(12), 5877-5882 (1977)... 

W. F. Murphy, /. Chem. Phys., 67, 5877 (1977). The Rayleigh Depolarization Ratio and Rotational Raman Spectrum of Water Vapor and the Polarizability Components for the Water Molecule. 

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