Terahertz absorption spectrum of para and ortho water vapors at different humidities at room temperature
Terahertz time-domain spectroscopy has been used to measure the absorption of water vapor in 0.2–2.4 T Hz range from low to high humidity at room temperature. The observed absorption lines are due to the water molecular rotations in the ground vibrational state. We find that the absorption strength of para transitions increases as humidity increases, while the absorption strength of ortho transitions increases and then decreases in intensity with increasing humidity. We explain this difference based on the nuclear spin statistics based ratio of ortho to para water monomer populations at room temperature. The preferential adsorption on the solid surfaces of para water leads to an ortho dominated vapor cloud whose monomer rotational absorption intensity decreases due to the effects of dimerization, molecular collisions, clustering, and interactions with liquid droplets at high concentrations.
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in [Terahertz absorption spectrum of para and ortho water vapors at different humidities at room temperature. Journal of Applied Physics 100, 9 (2006)] and may be found at https://doi.org/10.1063/1.2357412.
Files
Metadata
Work Title | Terahertz absorption spectrum of para and ortho water vapors at different humidities at room temperature |
---|---|
Access | |
Creators |
|
License | In Copyright (Rights Reserved) |
Work Type | Article |
Publisher |
|
Publication Date | November 8, 2006 |
Publisher Identifier (DOI) |
|
Deposited | January 22, 2024 |
Versions
Analytics
Collections
This resource is currently not in any collection.