Phenomena Induced by Intermolecular Interactions

This book is concerned with recent experimental and theoretical work dealing with phenomena created by the transient dipoles and polarizabilities produced by intermolecular interactions. The for­ mer produce absorption from the microwave to the optical regions of the spectrum and the latter produce Rayleigh and Raman scattering; such absorption and scattering would be absent without collisions. Static properties, such as dielectric constant, refractive index, and Kerr effect, also exhibit the effects of induced dipoles and polarizabilities. The first observation of an infrared absorption spectrum pro­ duced by the collisions of molecules which ordinarily do not have an allowed dipole transition was reported in 1949 (Crawford, Welsh, and Locke). The first observation of depolarized Rayleigh spectra due to collisions in atomic gases appeared in 1968 (McTague and Birnbaum). However, it was not until 1977 that the first conference dealing with collision-induced phenomena was organized by J. D. Poll at the University of Guelph. This conference was mainly concerned with studies of collision-induced absorption in gases. Light scat­ tering received more attention at the second meeting of the colli­ sion-induced community in 1978, at the E. Fermi Summer School on "Intermolecular Spectroscopy and Dynamical Properties of Dense Sys­ tems," organized by J. Van Kranendonk. However, the emphasis was still on collision-induced absorption in compressed gases, although some work on liquids, solid H , and related subjects such as ro­ 2 tational relaxation was included. The third induced phenomena con­ ference, organized by F.

Section 1: Compressed Gases and the Effect of Density.- A. Far Infrared and Infrared Absorption.- Classical Multipole Models: Comparison with Ab Initio and Experimental Results.- Ab Initio Calculations of Collision Induced Dipole Moments.- A Comparative Study of the Dielectric, Refractive and Kerr Virial Coefficients.- The Infrared and Raman Line Shapes of Pairs of Interacting Molecules.- Collision-Induced Absorption in the Microwave Region.- Collision-Induced Absorption in N2 at Various Temperatures.- Far Infrared Absorption Spectra in Gaseous Methane from 138 to 296 K.- Induced Vibrational Absorption in the Hydrogens.- Simultaneous Transitions in Compressed Gas Mixtures.- Molecular Motions in Dense Fluids from Induced Rotational Spectra.- Intercollisional Interference — Theory and Experiment.- Workshop Report: Infrared Absorption in Compressed Gases.- B. Light Scattering.- Ab Initio and Approximate Calcuations of Collision-Induced Polarizabilities.- Depolarization Ratio of Light Scattered by a Gas of Isotropic Molecules.- Depolarized Interaction Induced Light Scattering Experiments in Argon, Krypton, Xenon.- Interaction Induced Rotational Light Scattering in Molecular Gases.- Workshop Report: Light Scattering in Compressed Gases.- Section 2: Liquids and Liquid State Interactions.- A. Atomic Systems.- Theory of Collision-Induced Light Scattering and Absorption in Dense Rare Gas Fluids.- Calculation of Spectral Moments for Induced Absorption in Liquids.- B. Molecular Systems.- Interaction-Induced Vibrational Spectra in Liquids.- Far Infrared Induced Absorption in Highly Compressed Atomic and Molecular Systems.- Theoretical Interpretation of the Far Infrared Absorption Spectrum in Molecular Liquids: Nitrogen.- Molecular Dynamics Studies of Interaction Induced Absorption and Light Scattering in Diatomic Systems.- Interaction Induced Light Scattering from Tetrahedral Molecules.- Local Fields in Liquids.- Pressure — An Essential Experimental Variable in Spectroscopic Studies of Liquids.- Workshop Report: Liquids and Liquid State Interactions.- Section 3: Solid State, Amorphous, and Ionic Systems.- Study of the Collective Excitations in H2 as Observed in Far Infrared Absorption.- Induced Light Scattering in Disordered Solids.- Infrared Induced Absorption of Nitrogen and Methane Adsorbed in NaA Synthetic Zeolite.- Charge Induced Effects in Solid Tritium and Deuterium.- Workshop Reports: Some Considerations on Spectra Induced by Intermolecular Interactions in Molecular Solids and Amorphous Systems.- Section 4: Induced Transitions in Allowed Spectra.- Collision-Induced Effects in Allowed Infrared and Raman Spectra of Molecular Fluids.- Raman Scattering from Linear Molecules.- The Interference of Molecular and Interaction-Induced Effects in Liquids.- Interaction Induced Spectra of “Large” Molecules in Liquids.- The Infrared Spectrum of HD.- Workshop Report: The Interference of Induced and Allowed Molecular Moments in Liquids.- Section 5: Related Subjects.- Contribution of Bound Dimers, (N2)2, to the Interaction Induced Infrared Spectrum of Nitrogen.- Vibrational Spectral Lineshapes of Charge Transfer Complexes.- Collision-Induced Effects in Planetary Atmospheres.- Time-Domain Separation of Collision Induced and Allowed Raman Spectra.- Collision-Induced Radiative Transitions at Optical Frequencies.- Comments on Hyper-Rayleigh Scattering.- Comments on the Spectra of the Halogens and Halogen Complexes in Solution.- Author index.- Chemical index.