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1.
《Journal of Molecular Spectroscopy》1986,118(1):96-102
Using Fourier transform spectra, the intensities of 428 weak lines belonging to the ν1 + 2ν2, 2ν2 + ν3, 2ν1, ν1 + ν3, 2ν3, and ν1 + ν2 + ν3 − ν2 bands of the H216O molecule have been measured, between 6300 and 7900 cm−1, with an average uncertainty of 7%. 相似文献
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3.
《Journal of Molecular Spectroscopy》1987,125(2):393-412
Ionization-detected stimulated Raman spectroscopy was used to obtain high-resolution recordings of the two perpendicular bands of the benzene molecule centered at 1591.327 and 1609.518 cm−1. The effective resolution was further enhanced by deconvolving the spectrum to a linewidth 0.003 to 0.004 cm−1. Fine-tuning of the ionizing radiation made it possible to record the transitions belonging to each band separately, thus greatly simplifying the spectrum in the region of overlap. The strong sS and oO branches were, for the most part, completely resolved as were many lines in the weaker oP and sR branches and even in the central oQ and sQ branches. The observed bands belong to the E2g fundamental ν16 in nearly exact Fermi resonance with the combination ν2 + ν18. A detailed rovibrational analysis of the spectrum is reported. A perturbation detected in the sSk branches of the lower-frequency band for K = 19 to 23 was identified as a quintic anharmonic resonance with the third overtone, 4ν20, of the lowest lying fundamental ν20, which is infrared- and Raman-inactive (species E2u). Deperturbed spectroscopic constants for the interacting states are reported which reproduce the observed line positions with a standard deviation of 0.0013 cm−1. The unperturbed origins of the ν16 and ν2 + ν18 states are only 1.106 cm−1 apart. The fundamental ν16 was identified with the higher-frequency state with origin at 1600.976 cm−1. 相似文献
4.
《Journal of Molecular Spectroscopy》1987,123(1):145-160
An infrared laser sideband spectrometer operating in the CO2 laser region with 8- to 18-GHz sidebands has been used to record 266 transitions in the ν3 band and 84 transitions in the 2ν3 ← ν3 band of 12CH3F. The accuracy of the measured frequencies is estimated to be 1–3 MHz. A millimeter/submillimeter-wave spectrometer has been used to record the spectra of 48 pure rotational transitions in the ground vibrational state and 55 transitions in the v3 = 1 vibrational state with an accuracy of 20–90 kHz. The new measurements have been combined with previous radio frequency and infrared laser results to derive sets of constants for the ground, v3 = 1, and v3 = 2 states for this molecule. Tables of the vibrational dependence of the parameters and of the near coincidences of the ν3 and 2ν3 ← ν3 band transitions with CO2 laser frequencies are given. 相似文献
5.
《Journal of Molecular Spectroscopy》1987,122(2):365-370
The spectra of the 2ν1 + ν3 and 3ν3 bands of 14N16O2 have been recorded by means of high-resolution Fourier transform spectroscopy and have been extensively analyzed. The (2 0 1) and (0 0 3) rotational levels deduced from the analysis have been reproduced within the experimental uncertainty using a Hamiltonian which takes into account the Coriolis interaction coupling the vibrational states of the diads {(2 2 0), (2 0 1)} and {(0 2 2), (0 0 3)}. Finally, precise sets of vibrational energies, and spin-rotation, rotational, and coupling constants have been derived for these vibrational states. 相似文献
6.
Analysis of the Vibrational-Rotational Structure of 2ν1, ν1 + ν3, and 2ν3 Bands of the D2Se Molecule
Zhabina E. A. Onopenko G. A. Ulenikov O. N. Burger G. Jerzembeck W. 《Russian Physics Journal》2002,45(5):483-487
The absorption spectrum of the D2Se molecule in the region of 21, 1 + 3, and 23 absorption bands is registered with a high-resolution Fourier spectrometer and is studied theoretically for a Hamiltonian model with allowance for resonant interactions among (200), (101), and (002) vibrational states. 相似文献
7.
J.-M. Flaud W.J. Lafferty R.L. Sams 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(9-10):669-674
Using both high resolution (0.0018 cm?1) and medium resolution (0.112 cm?1) Fourier transform spectra of an enriched 34S (95.3%) sample of sulfur dioxide, it has been possible to accurately measure a large number of individual line intensities for some of the strongest of the SO2 bands, i.e. ν1, ν3 and ν1+ν3. These intensities were least-squares fitted using a theoretical model which takes into account the vibration–rotation interactions linking the upper energy levels where needed, and, in this way, expansions of the various transition moment operators were determined. The Hamiltonian parameters determined in previous analyses together with these moments were then used to generate synthetic spectra for the bands studied and their corresponding hot bands providing one with an extensive picture of the absorption spectrum of 34SO2 in the spectral domains, 8.7, 7.4, and 4 μm. 相似文献
8.
《Journal of Molecular Spectroscopy》1987,124(2):437-442
Infrared measurements have been made on SO2 between 450 and 602 cm−1 with a resolution of 0.005 cm−1. The B-type bands due to the bending mode transitions 010-000 and 020-010 have been assigned and analyzed for the 32S16O2 molecule. A total of 3007 transitions were measured and fit for 32S16O2 with a standard deviation of 0.0004 cm−1. Ro-vibrational constants are given that fit the current measurements and the pure rotational transitions reported in the literature. 相似文献
9.
《Journal of Molecular Spectroscopy》1986,117(2):416-434
A large number of transitions in the ν3 and 2ν3 ← ν3 bands of 13CH3F have been recorded at Doppler-limited resolution by means of an infrared laser microwave sideband spectrometer. The sidebands were generated in a CdTe crystal that was simultaneously irradiated by a CO2 infrared laser and a high-power microwave source operating in the 8- to 18-GHz region. The J and K structures of the bands were well resolved except for the lowest K values. Frequencies of transitions involving J values up to 47 and K values up to 16 are reported. Vibration-rotation parameters for the v3 = 0, 1, and 2 states were obtained by fitting to the experimental frequencies. These parameters reproduce the experimental values with an rms deviation of 3.8 MHz for the fundamental band and 2.5 MHz for the hot band. 相似文献
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11.
《Journal of Molecular Spectroscopy》1987,121(1):150-166
The ν3 and 2ν80 parallel bands of propyne (methyl acetylene) at 2137.88 and 2066.33 cm−1 have been studied at 0.006 cm−1 resolution. Their Fermi resonance and interaction with the ν8 + 2ν9, ν7 + ν9, and ν8 + ν9 + ν10 levels have been investigated. Molecular constants were determined from the assignment of 1150 lines. However, the rms error of 0.0028 cm−1 showed the presence of additional perturbations which cannot be uniquely identified. 相似文献
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13.
Fundamental spectroscopical parameters of the weak ν1+3ν2
1-ν2
1+ν3 band of CO2 are reported using a high-resolution, direct-absorption spectrometer, based on a distributed feed-back diode laser emitting
at 2 μm. Line intensities and self-broadening coefficients have been measured for the first time with high accuracy, for nine
lines of the R branch, from R(44) up to R(59). Comparison with available data has been made, and a generally good agreement
has been found.
Received: 30 August 1999 / Published online: 24 March 2000 相似文献
14.
《Journal of Molecular Spectroscopy》1987,122(1):130-134
Numerous transitions belonging to the a2ν2 ← sν2 hot bands of 14NH3 and 15NH3 have been identified and assigned in the long-path Fourier transform spectra of ammonia. The data have been processed to obtain effective molecular parameters for the a2ν2 states of 14NH3 and 15NH3. 相似文献
15.
The infrared spectrum of isotopically pure CH2 79BrCl has been recorded at a resolution of 0.0025?cm?1 and 0.0023?cm?1 (FWHM) in the range 600–1600?cm?1 with a Bruker IFS 120 HR Fourier transform spectrometer in Wuppertal. Here we report the full rotational analysis of the ν3 and ν9 fundamentals of the most abundant species CH2 79Br35Cl . Improved ground state constants, up to quartic terms, have been obtained from ground state combination differences (GSCD) involving transitions of the fundamentals ν3, ν4, ν5 and ν9. Both ν3 and ν9 transitions were fitted to a Watson-type Hamiltonian in the S-reduction, yielding accurate molecular constants for the ν3 and ν9 excited states. Small local perturbations were observed in both bands. Prominent features in the spectra were assigned to the ν3 and ν9 fundamentals of the CH2 79Br37Cl isotopic species and the hot-bands ν3+ν6???ν6 and ν9+ν6???ν6 of CH2 79Br35Cl. 相似文献
16.
《Journal of Molecular Spectroscopy》1986,118(1):288-297
Fourier Transform infrared spectra of gaseous natural FClO3 and monoisotopic F35ClO3 have been recorded at 293 and 225 K with a resolution of 0.04 cm−1. Rotational J structure and, in part, K structure were resolved for the parallel fundamentals, combination bands, and overtones ν1, ν2, ν3, ν1 + ν2, ν1 + ν3, ν2 + ν3, 2ν1, 2ν2, and 2ν3. Band origins ν0, anharmonicity constants χij, and vibration-rotation interaction constants αiA and αiB have been determined. For F35ClO3, ν0 values are ν1 = 1063.238(6), ν2 = 716.814(6), and ν3 = 549.877(3) cm−1. No perturbation was found at the present level of accuracy. 相似文献
17.
O.N Ulenikov E.S Bekhtereva V.A Kozinskaia Jing-Jing ZhengSheng-Gui He Shui-Ming HuQing-Shi Zhu C LeroyL Pluchart 《Journal of Molecular Spectroscopy》2002,215(2):295-308
The high-resolution (0.005 cm−1) Fourier transform infrared spectrum of PH3 is recorded and analyzed in the region of the fundamental stretching bands, ν1 and ν3. The ν2+ν4 and 2ν4 bands are taken into account also. Experimental transitions are assigned to the ν1, ν3, ν2+ν4, and 2ν4 bands with the maximum value of quantum number J equal to 15, 15, 13, and 15, respectively. a1-a2 splittings are observed and described up to the value of quantum number K equal to 10. The analysis of a1/a2 splittings is fulfilled with a Hamiltonian model which takes into account numerous resonance interactions among all the upper vibrational states. 相似文献
18.
JING-JING ZHENG O. N. ULENIKOV G. A. ONOPENKO E. S. BEKHTEREVA SHENG-GUI HE XIANG-HUAI WANG 《Molecular physics》2013,111(11):931-937
The high resolution Fourier transform spectrum of the D20 (ν = ν1 + ν2/2 + ν3 = 3.5) polyad was analysed within the framework of the Hamiltonian model taking into account resonance interactions between the seven states (310), (211), (112), (013), (230), (131) and (032). Transitions belonging to the 2ν1 + ν2 + ν3, 3ν1 +ν2 and 3ν2 + 2ν3 bands were assigned in the experimentally recorded spectrum. This provided the possibility of obtaining spectroscopic parameters of the ‘visible’ states (211), (310) and (032) and of estimating the band centres, and the rotational and resonance interaction parameters of the ‘dark’ states (112) and (131). 相似文献
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The ν1 (A1, 1583.22 cm−1) and ν4 (E, 1615.33 cm−1) Si-D stretching bands of monoisotopic D3Si35Cl have been studied by FTIR spectroscopy with a resolution of 3.3×10−3 cm−1. We have assigned 2341 rovibrational lines for ν1 (Jmax=70, Kmax=19) and 6207 for ν4 (Jmax=75, Kmax=27). Both (ΔK=±1, Δ?=±1) and (ΔK=±2, Δ?=?1) interactions connect the v1=1 and v4=1 levels, the latter exerting moreover a weak ?(2, 2) interaction. These interactions were taken into account in a nonlinear least-squares fit, refining 29 free parameters with a standard deviation of 0.257×10−3 cm−1 over 6722 nonzero-weighted data. Blended lines and about 250 of the 330 lines belonging to the K=11 subband of ν1 and the KΔK=−6 subband of ν4 were zero-weighted because they are locally perturbed respectively by the neighboring upper states of the 2ν3+ν6 (E, 1561.95 cm−1) and 3ν3 (A1, 1604.81 cm−1) bands. Equivalent fits were obtained for altogether three different models obeying constraints according to the theory of unitary equivalent reductions of the rovibrational Hamiltonian. By means of a band contour simulation both the transition moment ratio |M1:M4|=0.67 and a positive sign of the Coriolis intensity perturbation were determined. 相似文献