Binary-collision-induced longitudinal relaxation in gas-phase Kr83

Zackary I. Cleveland; Thomas Meersmann

doi:10.1063/1.3029663

A generic test of gas phase isolated binary collision theories for vibrational relaxation at liquid state densities based on the rescaling properties of collision frequencies

The Journal of Chemical Physics ◽

10.1063/1.458800 ◽

1990 ◽

Vol 93 (5) ◽

pp. 3712-3713 ◽

Cited By ~ 27

Author(s):

M. E. Paige ◽

C. B. Harris

Keyword(s):

Gas Phase ◽

Vibrational Relaxation ◽

Liquid State ◽

Binary Collision ◽

State Densities

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Intermolecular interactions in nuclear magnetic resonance. XI. The 13C and proton medium shifts of CH4 in the gas phase and in solution

Canadian Journal of Chemistry ◽

10.1139/v77-419 ◽

1977 ◽

Vol 55 (16) ◽

pp. 3021-3030 ◽

Cited By ~ 22

Author(s):

Frans H. A. Rummens ◽

Frank M. Mourits

Keyword(s):

Gas Phase ◽

Field Model ◽

Binary Collision ◽

Reaction Field ◽

Proton Shift ◽

Equal Degree ◽

Statistical Mechanical Model ◽

Statistical Mechanical ◽

The Mean ◽

Shift Data

The 1H and 13C resonances of methane have been measured at 298 K, both as pure CH4 in the gas phase as function of the density as well as at low concentration in solution, using polar, non polar, isotropic, as well as magnetically anisotropic solvents. It is found that both the gas and the solution proton shift data can be readily understood in terms of the Van der Waals shielding σw and the mean-square field due to the dispersive interactions: [Formula: see text]. Either a macroscopic reaction field model or a binary collision statistical mechanical model for [Formula: see text] can be used with an approximately equal degree of success. Whereas the 13C gas phase shifts of CH4 are also proportional to the density, the 13C gas-to-solution shifts indicate that, apart from σw, there exists even in non-polar isotropic solvents another effect which is not proportional to [Formula: see text]. The present study also includes a new proposal regarding [Formula: see text], a discussion of anisotropy shielding σa in magnetically anisotropic solvents and a discussion of the effective B parameters (1H and 13C) of CH4 in the gas and the solution state.

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Residual Gas Reactions in the Electron Microscope: I. Qualitative Observations on the Water Gas Reaction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101207 ◽

1968 ◽

Vol 26 ◽

pp. 292-293

Author(s):

Richard E. Hartman ◽

Roberta S. Hartman ◽

Peter L. Ramos

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Gas Phase ◽

Absolute Temperature ◽

Residual Gas ◽

Gas Reactions ◽

Image Position ◽

The Right ◽

Water Gas ◽

Thinning Rate

The action of water and the electron beam on organic specimens in the electron microscope results in the removal of oxidizable material (primarily hydrogen and carbon) by reactions similar to the water gas reaction .which has the form:The energy required to force the reaction to the right is supplied by the interaction of the electron beam with the specimen.The mass of water striking the specimen is given by:where u = gH2O/cm2 sec, PH2O = partial pressure of water in Torr, & T = absolute temperature of the gas phase. If it is assumed that mass is removed from the specimen by a reaction approximated by (1) and that the specimen is uniformly thinned by the reaction, then the thinning rate in A/ min iswhere x = thickness of the specimen in A, t = time in minutes, & E = efficiency (the fraction of the water striking the specimen which reacts with it).

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Integration of Core-Edge Spectroscopy Methods for the Study of Polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016323x ◽

1996 ◽

Vol 54 ◽

pp. 154-155

Author(s):

E. G. Rightor

Keyword(s):

Excited State ◽

Polymer Blends ◽

Gas Phase ◽

Spatial Resolution ◽

High Spatial Resolution ◽

Electronic States ◽

Core Electron ◽

Bulk Solids ◽

Development Application

Core edge spectroscopy methods are versatile tools for investigating a wide variety of materials. They can be used to probe the electronic states of materials in bulk solids, on surfaces, or in the gas phase. This family of methods involves promoting an inner shell (core) electron to an excited state and recording either the primary excitation or secondary decay of the excited state. The techniques are complimentary and have different strengths and limitations for studying challenging aspects of materials. The need to identify components in polymers or polymer blends at high spatial resolution has driven development, application, and integration of results from several of these methods.

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