Microscopic particles, liquid phase chemical

Over the last few decades, it has become clear that the microscopic structure of the liquid phase has a direct influence on the thermodynamics and kinetics of chemical reactions[33-35]. One expects that similar relationships will hold in the inhomogeneous region. The microscopic structure of bulk liquids can be characterized experimentally and theoretically using the pair (and higher order) particle distribution functions, p-jlr r ) is the joint probability density of... 

The major area of application for solids and liquids is chemical fingerprinting and the identification of unknown compounds. For solids, Raman is also used for phase identification, following amorphous/crystalline transitions, measurement of stress and strain, and, in the microscope mode, the detection and analysis of defects, including particles during wafer processing. 

By particulate matter we refer to any substance, except pure water, that exists as a liquid or solid in the atmosphere under normal conditions and is of microscopic or submicroscopic size but larger than molecular dimensions. Among atmospheric constituents, particulate matter is unique in its complexity. Airbome particulate matter results not only from direct emissions of particles but also from emissions of certain gases that either condense as particles directly or undergo chemical transformation to a species that condenses as a particle. A full description of atmospheric particles requires specification of not only their concentration but also their size, chemical composition, phase (i.e., liquid or solid), and morphology. 

Electrons residing in molecular clusters can be viewed as microscopic probes of both the local liquid structure and the molecular dynamics of liquids, and as such their transitory existence becomes a theoretical and experimental metaphor for one of the major fundamental and contemporary problems in chemical and molecular physics, that is, how to describe the transition between the microscopic and macroscopic realms of physical laws in the condensed phase. Since this chapter was completed in the Spring of 1979, several new and important observations have been made on the dynamics and structure of e, which, as a fundamental particle interacting with atoms and molecules in a fundamental way, serves to assist that transformation for electronic states in disordered systems. In a sense, disorder has become order on the subpicosecond time-scale, as we study events whose time duration is shorter than, or comparable to, the period during which the atoms or molecules retain some memory of the initial quantum state, or of the velocity or phase space correlations of the microscopic system. This approach anticipated the new wave of theoretical and experimental interest in developing microscopic theories of... 

Classical dynamics has been used extensively over the past twenty years to aid in our microscopic understanding of chemical reactions and properites of matter. As our experience has grown, the complexity of the systems studied has expanded from simple atom-diatom collisions and hard sphere liquids to more complicated gas-phase reactants (see the chapters by Schatz and Eigersma in this book) and more realistic liquids. Dynamics calculations allow the determination of average experimental quantities, and at the same time, they give physical insight into the microscopic mechanisms. Results of the calculations are very visual, allowing one to picture the motion of particles. The variety of applications of classical dynamics in chemistry is evidenced by the contributions to this volume. 

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