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Permanent moments light scattering

Raman spectroscopy Is a form of vibrational spectroscopy which, like Infrared spectroscopy. Is sensitive to transitions between different vibrational energy levels in a molecule (1). It differs from Infrared spectroscopy In that Information Is derived from a light scattering rather than a direct absorption process. Furthermore, different selection rules govern the Intensity of the respective vibrational modes. Infrared absorptions are observed for vibrational modes which change the permanent dipole moment of the... [Pg.49]

As in the Rayleigh case, the pair polarizability results as well from nonlinear light scattering mechanisms (induced by hyperpolarizabilities and permanent multipole moments). For tetrahedral molecules nonlinear mechanisms contribute to some correlation functions listed in Table V—only those related to the depolarized spectrum and governed by double rotational transitions (QQ, QO, and 00). The nonlinear origin corrections Atp j7"1 j2 which must be added to the linear origin terms cp 1 °f Table V for a tetrahedral molecule are successively [17]... [Pg.299]

Thus, if the particle has no permanent dipole moment, the rise and decay signals of the birefringence are symmetrical [cf Eqs. (13) and (14)]. The rotational diffusion coefficient 9 is usually obtained directly from the decay curve, Eq. (14) and Eq. (11), together with the apparent hydrodynamic radius Vf, determined in light scattering experiments, can be used to obtain information about the size and eccentricity alb of the rotating ellipsoid. [Pg.441]

In this section we shall examine the problems posed for the interpretation of "allowed spectroscopic lineshapes by the simultaneous influence of permanent and induced moments. These problems are quite general they arise in dielectric spectroscopy, infra-red absorption and light scattering. [Pg.447]

From the directional dependence and the depolarization ratios of the scattered radiation, information may be gained on particular tensor elements of The method has the advantage over EFISH measurements that it is also applicable to noncentro-symmetric molecules that do not posses a permanent dipole moment, in particular to, octopolar molecules of symmetry D3 (such as tricyanomethanide [C(CN)3] ) or of symmetry Tj (such as CCI4). It is to be expected that progress in laser technology and light detection systems will further improve the applicability of the method. [Pg.447]


See other pages where Permanent moments light scattering is mentioned: [Pg.34]    [Pg.371]    [Pg.115]    [Pg.8]    [Pg.31]    [Pg.288]    [Pg.294]    [Pg.296]    [Pg.227]    [Pg.130]    [Pg.76]    [Pg.97]    [Pg.82]    [Pg.135]    [Pg.119]    [Pg.165]    [Pg.165]    [Pg.89]    [Pg.42]   
See also in sourсe #XX -- [ Pg.49 ]




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Permanent moments

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