کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9589501 1393808 2005 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Multispectrum analysis of 12CH4 from 4100 to 4635 cm−1: 1. Self-broadening coefficients (widths and shifts)
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Multispectrum analysis of 12CH4 from 4100 to 4635 cm−1: 1. Self-broadening coefficients (widths and shifts)
چکیده انگلیسی
The Lorentz self-broadening (halfwidths) and self-induced pressure-shift coefficients were measured for the first time in the octad region of methane. All spectra were recorded at 0.011 cm−1 resolution using the McMath-Pierce Fourier transform spectrometer located at the National Solar Observatory on Kitt Peak, Arizona. 12C-enriched CH4 gas samples at room temperature were used, and high signal-to-noise ratios of 2000:1 were achieved. The multispectrum nonlinear least squares fitting technique enabled us to fit simultaneously a total of 10 high-resolution laboratory absorption spectra consisting of six self-broadened and four air-broadened spectra. In this paper, we report the self-broadened widths and self-induced pressure shift coefficients for 1423 transitions belonging to five bands with a maximum J of 16. The numbers of measurements by bands are: 71 for ν2 + 2ν4, 202 for ν1 + ν4, 824 for ν3 + ν4, 58 for 2ν2 + ν4, and 268 for ν2 + ν3. The observed widths varied from 0.045 to about 0.090 cm−1 atm−1 at 296 K. The measured pressure-shift coefficients had values extending from about −0.020 to −0.005 cm−1 atm−1 at 298.3 ± 1.2 K. The results obtained for the broadening coefficients in the various bands were compared with each other and with measurements reported in the literature for other methane bands.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Spectroscopy - Volume 232, Issue 2, August 2005, Pages 231-246
نویسندگان
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