Determination of Laser Absorption Coefficients of Gas Mixtures using an Ab Initio MD Model
In an effort to study the laser induced dissociation of gas mixtures for an ongoing research project on diamond thin film coating using multiple lasers, it is necessary to determine the absorption coefficient of laser energy by CO2 gas. An ab initio molecular dynamics (AIMD) model is used to determine the laser absorption coefficient of CO2 gas as a function of laser wavelength and gas temperature. The translational, rotational, and vibration motions of molecules are all taken into account in our model. The intra-molecular potential energy is obtained by solving the Kohn-Sham equation. The Projector-Augmented Wave (PAW) exchange-correlation potential function is used in the ab initio calculation. Specific heat of the CO2 gas is also calculated. The calculated thermal properties of CO2 gas and the vibration spectrum of molecules are in good agreement with the experimental results. The calculated normalized absorption line shape CO2 gas is close to the experimental results.
Z. Liang et al., "Determination of Laser Absorption Coefficients of Gas Mixtures using an Ab Initio MD Model," Proceedings of the 2007 ASME International Mechanical Engineering Congress and Exposition (2007, Seattle, WA), American Society of Mechanical Engineers (ASME), Nov 2007.
2007 ASME International Mechanical Engineering Congress and Exposition, IMECE 2007 (2007: Nov. 11-15, Seattle, WA)
Mechanical and Aerospace Engineering
Keywords and Phrases
Kohn-Sham Equation; Ab Initio Molecular Dynamics Model; Carbon Dioxide Gas; Projector-Augmented Wave
Article - Conference proceedings
© 2007 American Society of Mechanical Engineers (ASME), All rights reserved.
15 Nov 2007