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Volumn 104, Issue 36, 2000, Pages 8432-8444

Atom-bond transition: Transferability of atomic length scales

Author keywords

[No Author keywords available]

Indexed keywords

BINDING ENERGY; CHEMICAL BONDS; EXCITONS; MATHEMATICAL MODELS; MOLECULAR STRUCTURE;

EID: 0034274046     PISSN: 10895639     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp001719w     Document Type: Article
Times cited : (15)

References (151)
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    • See Laughlin, R. B. Rev. Modem Phys. 1999, 71, 863 and references therein. This point was first driven home to the author in the context of interactions leading to fractional charges and fractional quantum Hall effect. A point that requires clarification (at least to the present author) is whether atomic Orbitals can ever be used for the description of molecular states when we cross a phase boundary between atomic and bonding states. Because of this, a formal connection between the present model and existing textbook level theories for chemical bonding such as valence band and molecular orbital descriptions, is not attempted. It is in any case seemingly unnecessary besides being beyond the author's present competence. The density functional approach need not suffer from such a philosophical problem.
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    • (b) It is well known that conservation of angular momentum may be violated when there is spin-orbit coupling. Our argument is the reverse of this, since we claim that spin-charge conversion is not favored because strict angular momentum conservation may be violated.
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    • Pauling's definition (see ref 14) of electronegativity is based on the observation of an extraionic energy term, A, which contributes to an additional bond energy of heteronuclear bonds. A is given by the difference between the actual bond energy D(M-X) of the heteronuclear bond and the arithmetic mean of the bond energies D(M-M) and D(X-X) of the corresponding homonuclear bonds Δ = O(M-X) - 0.5{D(M-M) + D(X-X). In such a definition, Δ is in the exothermic direction.
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    • univ, = 0 state. A quantitative relation between length scales describing ground-state properties and heat of formation is not anticipated.
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    • to be published. These relationships are applicable to binary compounds of multivalent metals when one considers the heat of formation per atom of the more electronegative element X. These equations, in their present form, are obviously not applicable to compounds of hydrogen.
    • Ganguly, P., to be published. These relationships are applicable to binary compounds of multivalent metals when one considers the heat of formation per atom of the more electronegative element X. These equations, in their present form, are obviously not applicable to compounds of hydrogen.
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    • G = 0.32 au) which seemingly contradicts the results of Pauling's electronegativity scales. Similarly, the PMMH principle (see ref 17) requires H to be the more electronegative atom in all M-H bonds. This aspect requires further clarification and will be discussed in a separate communication. Equations 33 and 34 are meant for illustrative purposes at the moment.
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    • X.
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    • note
    • s(X). For these large differences, the repulsive interactions between the M atoms may become important. At the same time, the distance between the metal atoms becomes comparable to that in the elements themselves. This could lead to direct M-M interactions, which eventually leads to a reduction in the value of the heat of formation which is referenced to the standard elemental state.
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    • note
    • l/2. The explanation of the shortening of multiple bonds as well as rationalizations of electronegativity scales will follow in another communication, once the premises of this communication find some acceptance.


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