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Acetone, ab initio calculations
Tetrahedron, 1972Abstract Ab initio calculations on acetone using a 5,2,2 (contracted to 3,1,1:1 for carbon and oxygen, and 1 for hydrogen) Gaussian basis set gives a molecular energy of - 190·68162 Hartrees. The methyls have hydrogen eclipsing oxygen in the ground state. The rotational barrier is 0·99 kcal/mole.
N.L. Allinger, null M.J. Hickey
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Molecular symmetry in Ab initio calculations
Journal of Computational Physics, 1987A scheme is presented for the construction of the Fock matrix in LCAO-SCF calculations and for the transformation of basis integrals to LCAO-MO integrals that can utilize several symmetry unique lists of integrals corresponding to different symmetric groups.
Madhavan, P. V., Whitten, J. L.
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AB Initio Calculations on Sulfonylmethyl Anions
Phosphorus, Sulfur, and Silicon and the Related Elements, 1994Abstract The role of negative hyperconjugation in the title compounds is elucidated by the results of quantum chemical ab initio calculations.
Gerhard Raabe +2 more
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Ab initio calculations of biomolecules
AIP Conference Proceedings, 1995Ab initio quantum mechanical calculations are valuable tools for interpretation and elucidation of elemental processes in biochemical systems. With the ab initio approach one can calculate data that sometimes are difficult to obtain by experimental techniques. The most popular computational theoretical methods include the Hartree‐Fock method as well as
Andrzej Leś, Ludwik Adamowicz
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Benzooxirene. Ab initio calculations
Journal of Molecular Structure: THEOCHEM, 1996Abstract Ab initio calculations have been performed on benzooxirene, the corresponding oxo carbene (“ketocarbene”), and the transition state linking the two. At the highest level used, QCISD(T)/6-31G ∗ //MP2(FULL)/6-1G ∗ with MP2(FULL)/ 6-31G ∗ zero point energy corrections, the relative energies of the oxirene, the transition state and the carbene
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2010
Ab initio calculations rest on solving the Schrodinger equation; the nature of the necessary approximations determines the level of the calculation. In the simplest approach, the Hartree-Fock method, the total molecular wavefunction Ψ is approximated as a Slater determinant composed of occupied spin orbitals.
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Ab initio calculations rest on solving the Schrodinger equation; the nature of the necessary approximations determines the level of the calculation. In the simplest approach, the Hartree-Fock method, the total molecular wavefunction Ψ is approximated as a Slater determinant composed of occupied spin orbitals.
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1998
Various difficulties of classical physics, including inadequate description of atoms and molecules, led to new ways of visualizing physical realities, ways which are embodied in the methods of quantum mechanics. Quantum mechanics is based on the description of particle motion by a wave function, satisfying the Schrodinger equation, which in its “time ...
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Various difficulties of classical physics, including inadequate description of atoms and molecules, led to new ways of visualizing physical realities, ways which are embodied in the methods of quantum mechanics. Quantum mechanics is based on the description of particle motion by a wave function, satisfying the Schrodinger equation, which in its “time ...
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Boron in ab initio calculations
Computational Materials Science, 1998Abstract Based on ab initio quantum chemical Hartee–Fock (HF) approximations, density functional theory (DFT) and LMTO-ASA methods, we have determined the geometric and electronic structures of atomic-scaled boron clusters, surfaces and nanotubes. The starting structures were constructed with the help of an `Aufbau principle', previously proposed for
Ihsan Boustani, Alexander Quandt
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Ab initioone-electron property calculations
Molecular Physics, 1980A series of one-electron properties, i.e. dipole, quadrupole, octupole moments, diamagnetic susceptibility, second moments and second moment anisotropies of charge distribution, electric field, electric field gradient, diamagnetic shielding, nuclear quadrupole coupling constant, have been obtained by ab initio S.C.F. calculations for the molecules COF2,
Brouckère, G. de +3 more
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