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The J = 1 ← 0 and J = 2 ← 1 transitions and the l-doubling transitions of J = 2 – 6 of 12CH3F in the ν2 and ν5 states were analyzed by taking into account the Coriolis interaction between the two modes. The molecular constants which are derived are: ν5 - ν2, 252 412 ± 112; , 25 611.60 ± 0.40; Aζ5, ?38 772 ± 116; , 25 432.52 ± 0.33; D, 21 838.4 ± 8.2; , 39.58 ± 0.30 MHz; in addition to a few other minor constants. The present result is completely consistent with the recent Raman data of Escribano, Mills, and Brodersen, J. Mol. Spectrosc.61, 249 (1976). Molecular constants in the ν3 and ν6 states have also been obtained: B3, 25 197.570 ± 0.020; B6, 25 418.917 ± 0.047; Aζ6ηJ, ?0.562 ± 0.030; |q6|, 8.70 ± 0.13 MHz. Errors are 2.5 times the standard deviations. 相似文献
105.
The cw dye laser excitation spectrum of the
vibronic transition of the HSO radical was observed between 16 420 and 16 520 cm−1 with Doppler-limited resolution, 0.03 cm−1. The HSO radical was produced by reaction of discharged oxygen with H2S or CH3SH. The observed spectra were assigned to 751 transitions of the K′a ← K″a = 2 ← 3, 1 ← 2, 0 ← 1, 1 ← 0, 2 ← 1, and 3 ← 2 subbands, and were analyzed to determine rotational constants, centrifugal distortion constants, and spin-rotation interaction constants with good precision. The signs of the spin-rotation interaction constants were determined for both the upper and the lower state from the observed spectra. The band origin obtained is 16 483.0252 (2.5σ = 0.0013) cm−1. The molecular constants which were determined reproduce the observed transitions with an average deviation of 0.0045 cm−1. 相似文献
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Mitsutoshi Tanimoto Shuji Saito Yasuki Endo Eizi Hirota 《Journal of Molecular Spectroscopy》1983,100(1):205-211
The microwave spectrum of the SiF radical was observed in both and of the ground vibronic state. The SiF radical was produced by a dc discharge either in a mixture or in a transient molecule SiF2 generated by the reaction of SiF4 with heated solid silicon. The latter gave twice as intense a spectrum. A least-squares fit to the observed spectrum showed the rotational constant and the centrifugal distortion constant to be 17 350.2752(63) and 0.03188(13) MHz, respectively, with three standard errors in parentheses applying to the last digits of the constants. The lambda-doubling parameter p0 was found to be negative, ?87.67 MHz, indicating that the 2Σ+ excited state contributions dominate over those of 2Σ?. All four hyperfine coupling constants a, b, c, and d were determined and were employed to discuss the unpaired-electron spin and orbital distributions in the SiF radical. 相似文献
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Akihiro Fukabori Takayuki Yanagida Federico Moretti Yuui Yokota Rayko Shimura Shuji Maeo Jan Pejchal Kei Kamada Akira Yoshikawa 《Radiation measurements》2010,45(3-6):453-456
Micro-pulling down (μ-PD) method allows to prepare single crystals quickly and relatively inexpensively. Since it is a melt growth and taking into account segregation phenomena, the μ-PD method allows also to obtain single crystals characterized by dopant concentration gradients. Especially, taking the advantage of the grown crystal high aspect ratio, it allows to prepare crystalline samples with variable and wide range concentrations of dopants. These samples can help in understanding the correlation between dopant concentration and luminescence properties. 相似文献