FTIR Measurements of N(2)-Induced Pressure Broadening of Allene (C(3)H(4)) in the nu(10) Band.

J Mol Spectrosc

Joint Center for Earth Systems Technology, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland, 21250

Published: December 1999

Nitrogen pressure-broadening coefficients have been measured in the 841 cm(-1) nu(10) band of allene (H(2)C&dbond;C&dbond;CH(2)). The high-resolution absorption infrared spectra were recorded by a FTIR spectrometer at a temperature of 201 K. The Voigt line profile, convolved with a sinc instrument function, was applied to the fit of the observed rovibrational lines. No regular J or K dependence of the broadening coefficients was observed for this strong symmetric-top-molecule band. The power-exponential-gap (PEG) fitting law and the infinite-order-sudden (IOS) scaling law were modified for the fit of the N(2)-broadening coefficients. The wavefunction mixing arising from the nu(10)/nu(9) Coriolis resonance was taken into account for the IOS law. A total of 180 broadening coefficients measured at 201 K were reproduced with an accuracy of 8.6 and 7.9% by the PEG and IOS laws, respectively. Copyright 1999 Academic Press.

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http://dx.doi.org/10.1006/jmsp.1999.7977DOI Listing

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