Polarizabilities molecular beams

The essential elements.of the experiment are a) an effusive molecular beam source, b) inhomogeneous deflecting electric polefaces, c) surface ionization detector, capable of translation in order to obtain the deflected beam pattern. 1, 2, are the distance from the source to the front of the polefaces, the length of the polefaces and the distance from the back of the polefaces to the detector, respectively. A general review of deflection methods for determining polarizabilities is given by Miller and Bederson (8). 

When an electric field gradient is applied on a molecular beam of molecules with a dipole moment or high polarizability, they can be focused or defocused, depending on their J, M (and K for symmetric top sjjecies) quantum states. This method was applied in studying the sjjectroscopy of vdW molecules or in aligning molecules before reacting them. - ... 

Dielectric and pressure virial coefficients of NzO have been measured at 6.5, 30.1, and 75.1 °C. The dipole moment, polarizability, and molecular quadrupole moment were determined to be 0.18 D, 3.03 x 1CT24 cm3, and 3.4 xlO 26 e.s.u. cm2, respectively.91 A lower limit of —0.15 0.1 eV has been calculated for the molecular electron affinity of N20, using molecular beam studies.92 The enthalpy-pressure behaviour for N20 along eleven isotherms in the vapour phase has been determined from measurements of the Joule-Thomson effect.91... 

The recent femtosecond experimental data on electron solvation in water (Gaudel et al., 1984, 1987) and observations in a mass spectroscopy on the formation of electrons stabilized in molecular beam clusters (Arbruster et al., 1984) has rekindled extensive interest on the microscopic details of the dynamics and structure of e in particular. Since the appearance of the visible spectrum of e has now been observed from the two photon photoionization of pure water (e.g., no dopant molecules or ions were present) we must focus on what responses can be Induced from the medium on this timescale. From our present databank, it is evident that following the instantaneous electronic polarizability (linear and nonlinear) response to the moving charge and/or field, it is the librational responses that must be the key motion. We assume, for the moment, that the lifetime of the autoionizing level in H2O is not a significant factor. As we have discussed elsewhere (Kenney-Wallace,... 

Backer, J. A. (1997). Molecular beam studies on semiconductor clusters polarizabilities and chemical bonding. Angewandte Chemie (International Edition in English), 36(13-14), 1390-1404. 

The fundamentals of the Raman effect can be understood by consideration of a classical model, in which an incident beam of radiation (i.e., laser beam, for all practical purposes, in flame diagnostics) passes through an ensemble of molecules. The resultant laser beam electric field distorts the electronic cloud distribution of each molecule, causing oscillating dipoles these induced dipoles are related to the incident laser beam electric field by the molecular polarizability. The dipoles, in turn, produce a secondary radiating field at essentially the same frequency as that for the incident beam. This radiation is termed Rayleigh scattering. 

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