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On the resonance theory
Wei Wu,Yirong Mo,Qianer Zhang +2 more
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TLDR
In this paper, the mathematical formulation of resonance theory is discussed and a new basis for an irreducible representation of the unitary group, called bonded tableau, can be constructed to describe a resonance structure correspondingly.Abstract:
In the present paper, the mathematical formulation of resonance theory is discussed. In fact, resonance theory is a representative form of the unitary group approach. Using the standard projection operator of the symmetric group, a new basis for an irreducible representation of the unitary group, called bonded tableau, can be constructed to describe a resonance structure correspondingly. The relationships between bonded tableau and Weyl tableaux and between valence bond and molecular orbital approaches are revealed. Finally, test calculations on ozone and benzene are performed.read more
Citations
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Valence bond theory for chemical dynamics.
TL;DR: This essay provides a perspective on several issues in valence bond theory: the physical significance of semilocal bonding orbitals, the capability ofValence bond concepts to explain systems with multireferences character, and the use of valence Bond theory to provide analytical representations of potential energy surfaces for chemical dynamics.
Journal ArticleDOI
Valence bond configuration interaction: A practical ab initio valence bond method that incorporates dynamic correlation
TL;DR: In this article, a post-VBSCF method, called valence bond configuration interaction (VBCI), is developed, which incorporates dynamic correlation by use of configuration interaction to improve the energy after a VBSCF calculation.
Journal ArticleDOI
Delocalization in allyl cation, radical, and anion
TL;DR: In this article, the allyl cation, radical, and anion with 6-31G* basis set were analyzed and the delocalization energies for the three allyl systems were analyzed.
Journal ArticleDOI
A practical valence bond method: A configuration interaction method approach with perturbation theoretic facility
TL;DR: A second‐order perturbation theory is utilized as a means of configuration selection, and lead to considerable reduction of the computational cost, with little or no loss in accuracy.
Journal ArticleDOI
VB-DFT: a nonempirical hybrid method combining valence bond theory and density functional energies
Wei Wu,Sason Shaik +1 more
TL;DR: In this paper, a nonempirical procedure is presented for combining the valence bond (VB) methodology with density functional theory (DFT), called VB-DFT, which is based on partitioning the system into two coupled electronic subsets, one treated by DFT and the other by VB theory.
References
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Journal ArticleDOI
The resonating valence bond state in La2CuO4 and superconductivity
TL;DR: The oxide superconductors, particularly those recently discovered that are based on La2CuO4, have a set of peculiarities that suggest a common, unique mechanism: they tend in every case to occur near a metal-insulator transition into an odd-electron insulator with peculiar magnetic properties.
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On the Non‐Orthogonality Problem Connected with the Use of Atomic Wave Functions in the Theory of Molecules and Crystals
TL;DR: In this article, the authors show that the overlap integrals are of essential importance in molecules and in crystals, instead of being negligible, and the problem is simply solved by considering the orthonormalized functions [open phi]μ, given by (21), as the real atomic orbitals.
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Wechselwirkung neutraler Atome und homöopolare Bindung nach der Quantenmechanik
W. Heitler,F. London +1 more
TL;DR: In this article, a charakteristische quantenmechanische Mehrdeutigkeit scheint geeignet zu sein, die verschiedenen Verhaltungsweisen zu umfassen, welche die Erfahrung liefert: Wasserstoff z. B. elastischer Reflexion, bei den Edelgasen dagegen nur die letztere.
Journal ArticleDOI
Group theoretical approach to the configuration interaction and perturbation theory calculations for atomic and molecular systems
TL;DR: In this paper, a formalism for the generation of spin-symmetry adapted configuration interaction (CI) matrices of the N −electron atomic or molecular systems, described by nonrelativistic spin-independent Hamiltonians, is presented.
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The Nature of the Chemical Bond. V. The Quantum‐Mechanical Calculation of the Resonance Energy of Benzene and Naphthalene and the Hydrocarbon Free Radicals
Linus Pauling,G. W. Wheland +1 more
TL;DR: In this article, it was shown that the dissociation of certain substituted ethanes into free radicals is due not to weakness of the carbon-carbon bond in the ethane but to the stabilization of the free radicals resulting from resonance among the structures in which the unpaired electron is located on the methyl carbon and those in which it is on other atoms (ortho, para, etc., to the methyl carbons).