Download or read book Collisional Effects on Molecular Spectra written by Jean-Michel Hartmann and published by Elsevier. This book was released on 2021-01-12 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas phase molecular spectroscopy is a powerful tool for obtaining information on the geometry and internal structure of isolated molecules and their interactions with others. It enables the understanding and description, through measurements and modeling, of the influence of pressure on light absorption, emission, and scattering by gas molecules, which must be taken into account for the correct analysis and prediction of the resulting spectra. Collisional Effects on Molecular Spectra: Laboratory Experiments and Models, Consequences for Applications, Second Edition provides an updated review of current experimental techniques, theoretical knowledge, and practical applications. After an introduction to collisional effects on molecular spectra, the book moves on by taking a threefold approach: it highlights key models, reviews available data, and discusses the consequences for applications. These include areas such as heat transfer, remote sensing, optical sounding, metrology, probing of gas media, and climate predictions. This second edition also contains, with respect to the first one, significant amounts of new information, including 23 figures, 8 tables, and around 700 references.Drawing on the extensive experience of its expert authors, Collisional Effects on Molecular Spectra: Laboratory Experiments and Models, Consequences for Applications, Second Edition, is a valuable guide for all those involved with sourcing, researching, interpreting, or applying gas phase molecular spectroscopy techniques across a range of fields. - Provides updated information on the latest advances in the field, including isolated line shapes, line-broadening and -shifting, line-mixing, the far wings and associated continua, and collision-induced absorption - Reviews recently developed experimental techniques of high accuracy and sensitivity - Highlights the latest practical applications in areas such as metrology, probing of gas media, and climate prediction

Download or read book Collisional Effects on Molecular Spectra written by Jean-Michel Hartmann and published by Elsevier. This book was released on 2008-08-12 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas phase molecular spectroscopy is a powerful tool for obtaining information on the geometry and internal structure of isolated molecules as well as on the interactions that they undergo. It enables the study of fundamental parameters and processes and is also used for the sounding of gas media through optical techniques. It has been facing always renewed challenges, due to the considerable improvement of experimental techniques and the increasing demand for accuracy and scope of remote sensing applications. In practice, the radiating molecule is usually not isolated but diluted in a mixture at significant total pressure. The collisions among the molecules composing the gas can have a large influence on the spectral shape, affecting all wavelength regions through various mechanisms. These must be taken into account for the correct analysis and prediction of the resulting spectra. This book reviews our current experimental and theoretical knowledge and the practical consequences of collisional effects on molecular spectral shapes in neutral gases. General expressions are first given. They are formal of difficult use for practical calculations often but enable discussion of the approximations leading to simplified situations. The first case examined is that of isolated transitions, with the usual pressure broadening and shifting but also refined effects due to speed dependence and collision-induced velocity changes. Collisional line-mixing, which invalidates the notion of isolated transitions and has spectral consequences when lines are closely spaced, is then discussed within the impact approximation. Regions where the contributions of many distant lines overlap, such as troughs between transitions and band wings, are considered next. For a description of these far wings the finite duration of collisions and concomitant breakdown of the impact approximation must be taken into account. Finally, for long paths or elevated pressures, the dipole or polarizability induced by intermolecular interactions can make significant contributions. Specific models for the description of these collision induced absorption and light scattering processes are presented. The above mentioned topics are reviewed and discussed from a threefold point of view: the various models, the available data, and the consequences for applications including heat transfer, remote sensing and optical sounding. The extensive bibliography and discussion of some remaining problems complete the text. - State-of-the-art on the subject - A bibliography of nearly 1,000 references - Tools for practical calculations - Consequences for other scientific fields - Numerous illustrative examples - Fulfilling a need since there is no equivalent monograph on the subject

Download or read book Collisional Effects in Atomic Spectra written by M. Harris and published by . This book was released on 1985 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Collision and Interaction Induced Spectroscopy written by G.C. Tabisz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collision-or interaction-induced spectroscopy refers to radiative transitions, which are forbidden in free atoms or molecules, but which occur in clusters of interacting atoms or molecules. The most common phenomena are induced absorption, in the infrared region, and induced light scattering, which involves inelastic scattering of visible laser light. The particle interactions giving rise to the necessary induced dipole moments and polarizabilities are modelled at long range by multipole expansions; at short range, electron overlap and exchange mechanisms come into play. Information on atomic and molecular interactions and dynamics in dense media on a picosecond timescale may be drawn from the spectra. Collision-induced absorption in the infrared was discovered at the University of Toronto in 1949 by Crawford, Welsh and Locke who studied liquid O and N. Through the 1950s and 1960s, 2 2 experimental elucidation of the phenomenon, particularly in gases, continued and theoretical underpinnings were established. In the late 1960s, the related phenomenon of collision-induced light scattering was first observed in compressed inert gases. In 1978, an 'Enrico Fermi' Summer School was held at Varenna, Italy, under the directorship of J. Van Kranendonk. The lectures, there, reviewed activity from the previous two decades, during which the approach to the subject had not changed greatly. In 1983, a highly successful NATO Advanced Research Workshop was held at Bonas, France, under the directorship of G. Birnbaum. An important outcome of that meeting was the demonstration of the maturity and sophistication of current experimental and theoretical techniques.

Download or read book Studies of Collisional Effects in Atomic Spectra written by Neville J. Bowman and published by . This book was released on 1979 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Collisional Effects in Atomic Spectra written by D. Michael J. Harris and published by . This book was released on 1985 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Collisional Effects in the Saturation Spectroscopy of Three Level Systems Theory and Experiment written by P. R. Berman and published by . This book was released on 1977 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document reports on a theoretical and experimental study of the influence of collisions on the saturation spectroscopy line shapes associated with three-level gas vapor systems. The study is carried out with the goal of gaining new information concerning (a) the collisional processes that occur in atomic vapors, (b) the nature of the interatomic potential between a ground state and an excited-state atom and (c) the possibility of collision-induced enhancement of the absorption of radiation by an atomic system. In each of these areas, new results are obtained.

Download or read book Advances in Molecular Vibrations and Collision Dynamics written by and published by Elsevier. This book was released on 1998-09-25 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume focuses on molecular clusters, bound by van der Waals interactions and hydrogen bonds. Twelve chapters review a wide range of recent theoretical and experimental advances in the areas of cluster vibrations, spectroscopy, and reaction dynamics. The authors are leading experts, who have made significant contributions to these topics.The first chapter describes exciting results and new insights in the solvent effects on the short-time photo fragmentation dynamics of small molecules, obtained by combining heteroclusters with femtosecond laser excitation. The second is on theoretical work on effects of single solvent (argon) atom on the photodissociation dynamics of the solute H2O molecule. The next two chapters cover experimental and theoretical aspects of the energetics and vibrations of small clusters. Chapter 5 describes diffusion quantum Monte Carlo calculations and non additive three-body potential terms in molecular clusters. The next six chapters deal with hydrogen-bonded clusters, reflecting the ubiquity and importance of hydrogen-bonded networks. The final chapter provides the microscopic theory of the dynamics and spectroscopy of doped helium cluster, highly quantum systems whose unusual properties have been studied extensively in the past couple of years.

Download or read book Collisional Effects in the Absorption Spectra of the Oxygen a Band and Nitric Oxide Fundamental Band written by Robert S. Pope and published by . This book was released on 1998-12 with total page 307 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fourier transform spectroscopy was used to measure pressure broadening coefficients in the absorption spectra of both the oxygen A band and the nitric oxide fundamental band. Oxygen spectra were recorded with O2, N2, CO, CO2, SF6 and noble gas collision partners, while nitric oxide spectra were recorded using noble gas collision partners. Pressure broadening coefficients were determined in the P and R branches for every resolved line for each of the fifteen collision pairs studied. In addition, broadening coefficients and qualitative evidence of line coupling were found for the Q branch of NO + Ar and pressure-induced line shifting coefficients were measured for O2 + Xe. Elastic and inelastic theories of pressure broadening were used to interpret the observed broadening coefficients. The elastic model showed a strong correlation between the magnitude of the coefficients and the polarizability and mass of the perturber. The inelastic contribution to pressure broadening was modeled using both angular-momentum-based and energy-based fitting laws. The ECS-P and EPGL-O laws provided the best fits to the data. The results indicate that the inelastic component is an important contribution to collisional broadening in diatomic molecules and that angular-momentum transfer is a plausible governing mechanism for the inelastic collisions.

Download or read book Collision induced Absorption in Gases written by Lothar Frommhold and published by . This book was released on 1993 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the theory and experiment of collision-induced absorption of infrared radiation in dense gases.

Download or read book Molecular and Laser Spectroscopy written by Zu-Geng Wang and published by . This book was released on 1991 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Velocity changing Collisional Effects in Nonlinear Atomic Spectroscopy and Photon Echo Decay in Gases written by Roger M. Herman and published by . This book was released on 1983 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Molecular Spectroscopy Modern Research written by K. Narahari Rao and published by . This book was released on 1972 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Control and Spectroscopic Studies of Collisional Population Transfer in Molecular Electronic States written by S. W. Poon and published by . This book was released on 2017 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: The quantum interference effects, such as the Autler-Townes (AT) effect and electromagnetically induced transparency (EIT) applied to molecular systems are the focus of this Dissertation in the context of high resolution molecular spectroscopy. We demonstrate that the AT effect can be used to manipulate the spin character of a spin-orbit coupled pair of molecular energy levels serving as a \textit{gateway} between the singlet and triplet electronic states. We demonstrate that the singlet-triplet mixing characters of the \textit{gateway} levels can be controlled by manipulating the coupling laser \textit{E} field amplitude. We observe experimentally the collisional population transfer between electronic states $G^1\Pi_g (v=12, J=21, f)$ and $1^3\Sigma _g^-(v=1, N=21, f)$ of $^7$Li$_2$. We obtain the Stern-Vollmer plot according to the vapor pressure dependence of collisional transfer rate. The triplet fluorescence from the mixed \textit{gateway} levels to the triplet $b^3\Pi_u(v'=1,J'=

Download or read book Spectral Line Shapes written by Marco A. Gigosos and published by American Institute of Physics. This book was released on 2008-11-04 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: This biennial conference is the main international forum for both fundamental and applied works dealing with processes related to the formation of the spectral line profiles and with their use for diagnostic purposes. On the fundamental side, the study of the line profiles reveals the underlying atomic and molecular interactions. On the practical side, the line profiles are employed as powerful diagnostic tools for various media, such as neutral gases, technological gas discharges, magnetically-confined plasmas for fusion, laser- and Z-pinch-produced plasmas, astrophysical plasmas, and planetary atmospheres.

Download or read book Compendium of Surface and Interface Analysis written by The Surface Science Society of Japan and published by Springer. This book was released on 2018-02-19 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book concisely illustrates the techniques of major surface analysis and their applications to a few key examples. Surfaces play crucial roles in various interfacial processes, and their electronic/geometric structures rule the physical/chemical properties. In the last several decades, various techniques for surface analysis have been developed in conjunction with advances in optics, electronics, and quantum beams. This book provides a useful resource for a wide range of scientists and engineers from students to professionals in understanding the main points of each technique, such as principles, capabilities and requirements, at a glance. It is a contemporary encyclopedia for selecting the appropriate method depending on the reader's purpose.

Download or read book Collisional Effects in the Spectrum of Rubidium written by Mohammed Saleem Awan and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: