- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Extended analysis of FTIR high resolution spectra of HD32S and HD34S in the region of the ν2 band: Positions and strengths of individual lines
摘要： The high resolution infrared spectra of deuterated hydrogen sulfide HDS were recorded with a Bruker IFS125HR Fourier transform infrared spectrometer (Zurich prototype ZP2001) and analyzed in the ν2 fundamental band region, 690–1510 cm?1. 2684 transitions with maximum values of the quantum numbers Jmax.=25 and Kmax.a=17 were assigned in the experimental spectra to the ν2 band (compared to Jmax.=22 and Kmax.a=10 in the preceding analogous studies) of HD32S. On this basis, 415 upper ro–vibrational energies were obtained, which were used then in the weighted fit of the Watson Hamiltonian parameters. 33 parameters obtained from the fit reproduce the 415 initial energy values with a root mean square deviation drms=1.1×10?? cm?1. An analysis of 418 experimental ro–vibrational line intensities of the ν2 band of HD32S was made using the Hartmann–Tran profile of individual lines, and results were applied in the fit of parameters of the effective dipole moment operator. Isotopic relations for the dipole moment parameters were derived and used for the fit procedure. The obtained 'model' parameters reproduce the initial line strengths with the drms=4.7%. A list of 2684 experimental transitions of HDS is generated together with the presentation of their individual line strengths predicted on the basis of the obtained effective dipole moment parameters. An analogous analysis was fulfilled for the ν2 band of the HD3?S isotopologue.
关键词： HD32S,isotopic substitution,FTIR,ν2 band,line positions,HD34S,high resolution spectra,line strengths,spectroscopic parameters
更新于2025-09-23 15:23:52
-
Theoretical spectroscopic parameters for isotopic variants of HCO <sup>+</sup> and HOC <sup>+</sup>
摘要： Theoretical spectroscopic parameters are derived for all isotopologues of HCO+ and HOC+ involving H, D, 16O, 17O, 18O, 12C, and 13C by means of a two-step procedure. Full-dimensional rovibrational calculations are first carried out to obtain numerically exact rovibrational energies for J = 0–15 in both parities. Effective spectroscopic constants for the vibrational ground state, ν1, ν2, and ν3 are determined by fitting the calculated rovibrational energies to appropriate spectroscopic Hamiltonians. Combining our vibration-rotation corrections with the available experimental ground-state rotational constants, we also derive the new estimate for the equilibrium structure of HCO+, re(CH) = 1.091 98 ? and re(CO) = 1.105 62 ?, and for the equilibrium structure of HOC+, re(HO) = 0.990 48 ? and re(CO) = 1.154 47 ?. Regarding the spectroscopic parameters, our estimates are in excellent agreement with available experimental results for the isotopic variants of both HCO+ and HOC+: the agreement for the rotational constants Bv is within 3 MHz, for the quartic centrifugal distortion constants Dv within 1 kHz, and for the effective ?-doubling constants qv within 2 MHz. We thus expect that our results can provide useful assistance in analyzing expected observations of the rare isotopologues of HCO+ and HOC+ that are not yet experimentally known.
关键词： HOC+,rovibrational calculations,HCO+,equilibrium structure,spectroscopic parameters,isotopic variants
更新于2025-09-23 15:23:52
-
Measurements of spectroscopic parameters of CO2 transitions for Voigt, Rautian, Galatry and speed-dependent Voigt profiles near 1.43 μm using the WM-DAS method
摘要： Linestrengths, self-broadening and narrowing coefficients for 8 absorption transitions of CO2 near 1.43 μm were measured using the wavelength modulation direct absorption spectroscopy (WM-DAS) at 300-1000 K and 5-20 kPa. The SNR was enhanced to 1500 for the peak absorbance around 5% at room temperature and remains at 550 for the peak absorbance around 1% at high temperatures by use of the WM-DAS method. The Voigt, Rautian, Galatry and quadratic speed-dependent Voigt profiles were used to recover the absorbance and retrieve the best-fit spectroscopic parameters and their temperature dependence. The quadratic speed-dependent Voigt profile was found to give the best combination of accuracy and robust lineshape parameters. The measured linestrengths and self-broadening coefficients compare well with the available values listed in the HITRAN/HITEMP database. The self-narrowing coefficients were also determined for GP, RP and qSDVP with analyses of the uncertainties in these spectroscopic parameters.
关键词： WM-DAS method,Galatry profile,speed-dependent Voigt profile,Voigt profile,spectroscopic parameters,Rautian profile,CO2
更新于2025-09-10 09:29:36
-
Extended analysis of the FTIR high–resolution spectrum of D232S in the region of the ν2 band
摘要： The high resolution infrared spectra of dideuterated hydrogen sulfide D2S were recorded with a Bruker IFS 125HR Fourier transform infrared spectrometer (Zürich prototype ZP2001) and analyzed in the ν2 fundamental band region, 750–1200 cm?1. The 1742 transitions (which is more than two times more than in the preceding analogous studies) were assigned in the experimental spectra to the ν2 band (the maximum values of the quantum numbers are Jmax = 30 and Kmaxa = 21). The subsequent weighted fit of experimentally assigned transitions was made with the Watson Hamiltonian, resulting in a set of 34 parameters which reproduces the initial 535 infrared ro–vibrational energy values from 1742 experimental line positions with a root mean square deviation drms = 1.31 × 10?4. An analysis of 280 experimental ro–vibrational line intensities (324 transitions) of the ν2 band was made using the Hartmann–Tran profile of individual lines, and the results were applied then in the fit of parameters of the effective dipole moment operator. Isotopic relations for the dipole moment parameters were derived and used for the fit procedure. The obtained “model dependent” parameters reproduce the initial line strengths with the drms = 2.5%. A list of 1742 experimental transitions of D2S is generated together with the presentation of their individual line strengths calculated on the basis of the obtained effective dipole moment parameters.
关键词： D2S high resolution spectra,v2 band: line positions and strengths,Spectroscopic parameters
更新于2025-09-04 15:30:14