Results 241 to 250 of about 32,342 (259)
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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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Journal of Molecular Structure, 1992
Abstract Shielding constants of nuclear charge can be considered as a principle unifying the theory of BOHR and the WAVE-MECHANICAL theory. Spectroscopic maxima are explained in this paper in terms of molecular-orbital electron transitions in comparison with calculations of wave numbers, by the aid of shielding constants.
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Abstract Shielding constants of nuclear charge can be considered as a principle unifying the theory of BOHR and the WAVE-MECHANICAL theory. Spectroscopic maxima are explained in this paper in terms of molecular-orbital electron transitions in comparison with calculations of wave numbers, by the aid of shielding constants.
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Journal of the Chemical Society, Faraday Transactions 2, 1987
The evaluation of analytic gradients and higher derivatives has had a tremendous impact on quantum chemistry. Although self-consistent field (SCF) first derivatives and higher derivatives are now routinely evaluated as ‘black-box’ procedures, derivatives of correlated wavefunctions are not.
Nicholas C. Handy +2 more
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The evaluation of analytic gradients and higher derivatives has had a tremendous impact on quantum chemistry. Although self-consistent field (SCF) first derivatives and higher derivatives are now routinely evaluated as ‘black-box’ procedures, derivatives of correlated wavefunctions are not.
Nicholas C. Handy +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, 1964
A set of single-configuration self-consistent field molecular orbital wavefunctions for the 1Σ ground state of BeO is presented. A potential curve which is approximately 0.3 eV above the Hartree—Fock potential curve for the molecule is presented, together with the results of a spectroscopic analysis on it.
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A set of single-configuration self-consistent field molecular orbital wavefunctions for the 1Σ ground state of BeO is presented. A potential curve which is approximately 0.3 eV above the Hartree—Fock potential curve for the molecule is presented, together with the results of a spectroscopic analysis on it.
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Spectroscopic constants and molecular properties of , A2Πu, and D2Πg electronic states of the ion
Computational and Theoretical Chemistry, 2011Deheng Shi +4 more
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Molecular structure and spectroscopic properties of two radicals of C4H2N: a DFT study
Journal of Molecular Modeling, 2023Meishan Wang +2 more
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