Results 141 to 150 of about 30,690 (171)
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Journal of Molecular Spectroscopy, 1984
A new determination of the potential energy function of the carbon dioxide molecule from its vibrorotational spectrum is presented. Starting from the previous determination made by A. Chedin [J. Mol. Spectrosc. 76, 430–491 (1979)] and from a significantly larger set of updated experimental data, the new potential is shown to provide a better agreement ...
Alain Chedin, Jean-Luc Teffo
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A new determination of the potential energy function of the carbon dioxide molecule from its vibrorotational spectrum is presented. Starting from the previous determination made by A. Chedin [J. Mol. Spectrosc. 76, 430–491 (1979)] and from a significantly larger set of updated experimental data, the new potential is shown to provide a better agreement ...
Alain Chedin, Jean-Luc Teffo
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Journal of Molecular Structure, 1981
Abstract Microwave spectra of thionyl chloride, SO35Cl2 and SO35Cl37Cl, in the frequency range 8–25 GHz have been analyzed. The rotational constants have been obtained from the low J transition frequencies. The rS coordinates of Cl atoms and the ro structure have been evaluated with some assumptions: r(S-O) = 1.435 ± 0.011± A, r(S—Cl) = 2.072 0.005 A,
Sigenari Suzuki +5 more
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Abstract Microwave spectra of thionyl chloride, SO35Cl2 and SO35Cl37Cl, in the frequency range 8–25 GHz have been analyzed. The rotational constants have been obtained from the low J transition frequencies. The rS coordinates of Cl atoms and the ro structure have been evaluated with some assumptions: r(S-O) = 1.435 ± 0.011± A, r(S—Cl) = 2.072 0.005 A,
Sigenari Suzuki +5 more
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Molecular Physics, 2003
The electronic structure of the ScN and ScP molecules is a subject of controversy and turns out to be a challenging problem in quantum chemistry. We show that the ground-state electronic structure for both molecules depends critically on the choice of methods used which incorporate different ways of accounting for electron correlation.
ABDELALI DAOUDI +4 more
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The electronic structure of the ScN and ScP molecules is a subject of controversy and turns out to be a challenging problem in quantum chemistry. We show that the ground-state electronic structure for both molecules depends critically on the choice of methods used which incorporate different ways of accounting for electron correlation.
ABDELALI DAOUDI +4 more
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Journal of Molecular Spectroscopy, 1980
Abstract The rotational spectrum of isothiocyanic acid was measured for the isotopically enriched species H15NCS and HN13CS as well as HNC34S in natural abundance. In the frequency range from 8 to 240 GHz the a-type R-branch transitions were measured for all three isotopic species.
Koichi Yamada +4 more
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Abstract The rotational spectrum of isothiocyanic acid was measured for the isotopically enriched species H15NCS and HN13CS as well as HNC34S in natural abundance. In the frequency range from 8 to 240 GHz the a-type R-branch transitions were measured for all three isotopic species.
Koichi Yamada +4 more
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International Journal of Quantum Chemistry, 2011
AbstractThe highly accurate valence internally contracted multireference configuration interaction (MRCI) approach has been employed to investigate the potential energy curves (PECs) for the X2Π, b4Σ−, C2Σ− states of PO and the X1Σ+ state of PO+. For these electronic states, the spectroscopic parameters of the isotopes (P16O, P18O, P16O+, and P18O ...
Jin‐Feng Sun +2 more
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AbstractThe highly accurate valence internally contracted multireference configuration interaction (MRCI) approach has been employed to investigate the potential energy curves (PECs) for the X2Π, b4Σ−, C2Σ− states of PO and the X1Σ+ state of PO+. For these electronic states, the spectroscopic parameters of the isotopes (P16O, P18O, P16O+, and P18O ...
Jin‐Feng Sun +2 more
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The Journal of Physical Chemistry, 1987
The authors describe the use of CARS spectroscopy of photofragments as a means of obtaining extensive spectroscopic constants and accurate potential curves. UV photodissociation of ozone yields O/sub 2/(a/sup 1/..delta../sub g/) in nu = 0-6 and J = 0-50.
Jong Chen. Nieh, James J. Valentini
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The authors describe the use of CARS spectroscopy of photofragments as a means of obtaining extensive spectroscopic constants and accurate potential curves. UV photodissociation of ozone yields O/sub 2/(a/sup 1/..delta../sub g/) in nu = 0-6 and J = 0-50.
Jong Chen. Nieh, James J. Valentini
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The Journal of Chemical Physics, 1961
Limited LCAO MO functions were computed for several diatomic molecules at four different values of the internuclear distance near Re, and the corresponding total energies fitted to a third degree polynomial in R. Spectroscopic constants ωe, ωexe, Be, αe, Re, ke were derived from the resulting potential curve and compared to observed values.
S. Fraga, B. J. Ransil
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Limited LCAO MO functions were computed for several diatomic molecules at four different values of the internuclear distance near Re, and the corresponding total energies fitted to a third degree polynomial in R. Spectroscopic constants ωe, ωexe, Be, αe, Re, ke were derived from the resulting potential curve and compared to observed values.
S. Fraga, B. J. Ransil
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1992
The coupled-cluster (CC) method,1–4 originally designed for closed-shell systems, has been extended to include open-shell systems, which cannot be described adequately by a single determinant.5–22 The basic approach of the multireference method is to define an effective Hamiltonian in a low-dimensional model (or P) space, with eigenvalues approximating
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The coupled-cluster (CC) method,1–4 originally designed for closed-shell systems, has been extended to include open-shell systems, which cannot be described adequately by a single determinant.5–22 The basic approach of the multireference method is to define an effective Hamiltonian in a low-dimensional model (or P) space, with eigenvalues approximating
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The use of singular value decomposition in the fitting of molecular constants to spectroscopic data
Journal of Molecular Spectroscopy, 1990Abstract Molecular spectroscopy aims at determining molecular parameters from spectroscopic data. The system of linear equations, the conditional equations, connecting the parameters and the experimental data is frequently nearly singular because some of the parameters are not too well defined by the experiment.
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Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2008
Abstract Ab initio multireference single- and double-excitation configuration interaction (MRD-CI) calculations have been carried out for magnesium oxide (MgO) and lithium oxide (LiO) and their positronic complexes. These results are compared with previous theoretical data obtained earlier for beryllium oxide (BeO) and the series of alkali hydrides ...
Robert J. Buenker +1 more
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Abstract Ab initio multireference single- and double-excitation configuration interaction (MRD-CI) calculations have been carried out for magnesium oxide (MgO) and lithium oxide (LiO) and their positronic complexes. These results are compared with previous theoretical data obtained earlier for beryllium oxide (BeO) and the series of alkali hydrides ...
Robert J. Buenker +1 more
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