On the Explosion of Homogeneous Gaseous Mixtures

ABSTRACTWe tried direct oxynitridation of silicon surfaces by remote-plasma-exited nitrogen and oxygen gaseous mixtures at 700°C in a high vacuum. The oxynitrided surfaces were investigated with in-situ X-ray photoelectron spectroscopy. With increase of the oxynitridation time, the surface density of nitrogen gradually increases, but that of oxygen shows nearly saturation behavior after the rapid increase in the initial stage. We also annealed the grown oxynitride and oxide films to investigate the role of the contained nitrogen. The desorption rate of oxygen from the oxynitride films is much less than that from oxide films. We confirmed that nitrogen stabilizes the thermal stability of these oxynitride films.

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The virial coefficients of the carbon dioxide-ethylene system I. Pure gases

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1964.0034 ◽

1964 ◽

Vol 277 (1371) ◽

pp. 448-467 ◽

Cited By ~ 35

Keyword(s):

Carbon Dioxide ◽

Second Virial Coefficient ◽

Virial Coefficients ◽

Direct Determination ◽

Expansion Method ◽

National Physical Laboratory ◽

Intermolecular Potential ◽

Gaseous Mixtures ◽

Physical Laboratory ◽

The Relationship

This paper describes the first part of an investigation of the thermodynamic properties of gases and gaseous mixtures undertaken a few years ago at the National Physical Laboratory, with the main object of providing data on the relationship between the properties of mixtures and those of the pure constituents. The virial coefficients of carbon dioxide and ethylene have been determined by the series-expansion method over the range —10 to 200 °C, and the representation of the results by several forms of intermolecular potential has been investigated. In the case of ethylene it appears that the second virial coefficient may be represented accurately in terms of a Lennard-Jones 6:12 potential, the parameters of which are determined. In the corresponding representation for carbon dioxide there is a small but systematic discrepancy and evidence is adduced that this may be rectified by the introduction of a quadrupole interaction term on the lines of the theory developed by Pople. The value of the quadrupole moment suggested by this calculation proves to be in fairly close agreement with a recent direct determination. Work on the virial coefficients of mixtures of the two gases will be described in a further paper.

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Donor-acceptor complexes formed by perfluoro-organo bromides and iodides with nitrogenous and other bases. II. Band shapes and widths in the absorption spectrum of gaseous CF3I-N(CH3)3

Australian Journal of Chemistry ◽

10.1071/ch9712493 ◽

1971 ◽

Vol 24 (12) ◽

pp. 2493 ◽

Cited By ~ 17

Author(s):

A Mishra ◽

ADE Pullin

Keyword(s):

Vibrational Mode ◽

Low Frequency ◽

Molecular Complexes ◽

Wave Number ◽

Centrifugal Distortion ◽

Band Shape ◽

Gaseous Mixtures ◽

Factors Affecting ◽

Donor Acceptor ◽

Vibration Rotation

The absorption band centred at c. 77 cm-1 in gaseous mixtures of CF3I and N(CH3)3 previously reported and attributed to the N-I stretching mode of the complex CF3I-N(CH3)3 has been carefully re-examined. This band is of interest as an example of a low frequency ?dissociative type? vibrational mode of a weak molecular complex. The band is asymmetric and apparently structureless with a half intensity width at room temperature of 28-30 cm-1. The width of the band may be accounted for as arising from transitions vi + vi+1 where vi is the vibrational quantum number of the N-I stretching mode with vi up to c. 10 making appreciable contribution to the intensity on the low wave-number side. Centrifugal distortion in the complex is considered. Centrifugal stretching and consequent weakening of the bond may shift the band envelope 2-3 cm-1 to lower wave numbers. Assessment of these and other factors affecting the band shape suggest that the fundamental frequency is probably c. 90 cm-1. The band shape of the vibrational mode of the complex at c. 272 cm-1 is briefly discussed. Many of the considerations presented in this paper should apply to vibration-rotation band shapes in other weak molecular complexes. Some general consequences of anharmonicity for the interpretation of the spectra of weak molecular complexes are discussed.

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