Date of Award
Master of Science
Department of Engineering Physics
Larry W. Burggraf, PhD
The rotation and vibration spectral properties including frequencies and intensities for highly concentrated molecules present in wildland and artificial fires have been studied. These properties were used to determine absorption and its effect in a link budget analysis. Absorption in link budget analyses is commonly accounted for via line-by-line methodology aided by HITRAN documented intensities. Limited, if any, customization of spectral properties is available with HITRAN and other spectral databases. Ab initio calculations with different atomic basis sets were employed to obtain structures, dipole moments, rotational-vibrational frequencies and intensities, as well as various coupling parameters. Anharmonic corrections to the vibrational energies are included in the calculations. The values of these parameters were found to be in agreement with experimental data while allowing flexibility for the inclusion or exclusion of various spectral properties. Discussed here is molecular absorption in relation to a link budget, an overview of vibration-rotation constants for various molecular geometries, a description of intensities calculated from transition dipole, and lastly power-loss due to absorption.
DTIC Accession Number
Husk, Matthew B., "Ab Initio Spectroscopy of Natural and Artificial Fire Contaminants for V/W Band Frequency Signal Absorbance" (2021). Theses and Dissertations. 5014.