Quantum Theory and Electron Pair Bond

By W. Heitler

doi:10.1103/physrev.38.243

Excitation energies with linear response density matrix functional theory along the dissociation coordinate of an electron-pair bond in N-electron systems

The Journal of Chemical Physics ◽

10.1063/1.4852195 ◽

2014 ◽

Vol 140 (2) ◽

pp. 024101 ◽

Cited By ~ 13

Author(s):

R. van Meer ◽

O. V. Gritsenko ◽

E. J. Baerends

Keyword(s):

Density Matrix ◽

Linear Response ◽

Electron Pair ◽

Pair Bond ◽

Electron Systems ◽

Excitation Energies ◽

Functional Theory

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The Carbon−Lithium Electron Pair Bond in (CH3Li)n(n= 1, 2, 4)

Organometallics ◽

10.1021/om950966x ◽

1996 ◽

Vol 15 (13) ◽

pp. 2923-2931 ◽

Cited By ~ 202

Author(s):

F. Matthias Bickelhaupt ◽

Nicolaas J. R. van Eikema Hommes ◽

Célia Fonseca Guerra ◽

Evert Jan Baerends

Keyword(s):

Electron Pair ◽

Pair Bond

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G. N. Lewis's Views on Bond Theory 1900–16

The British Journal for the History of Science ◽

10.1017/s0007087400014242 ◽

1975 ◽

Vol 8 (3) ◽

pp. 233-239 ◽

Cited By ~ 5

Author(s):

Robert E. Kohler

Keyword(s):

Electron Pair ◽

Inorganic Compounds ◽

Structural Formula ◽

Pair Bond ◽

Bond Theory ◽

Scientific Significance ◽

Structural Formulae ◽

Chemical Evidence

In a recent paper on the origin of G. N. Lewis's concept of the shared electron pair bond, I argued that the sources of Lewis's novel conception were certain ideas of J. J. Thomson and Alfred Parson. Yet the only influence that Lewis explicitly acknowledged was neither of these, but Alfred Werner's. The following statement appears in his book, Valence (1923):I still have poignant remembrance of the distress which I and many others suffered some thirty years ago in a class in elementary chemistry, where we were obliged to memorize structural formulae of a great number of inorganic compounds. Even such substances as the ferricyanides and ferryocyanides were forced into the system, and bonds were drawn between the several atoms to comply with certain artificial rules, regardless of all chemical evidence. Such formulae are now believed to be almost, if not entirely devoid of scientific significance. Such abuse of the structural formula inevitably led to a reaction which found its best expression in the publications of Werner. His Neuere Anschauungen … (1905) marked a new epoch in chemistry; and in attempting to clarify the fundamental ideas of valence, there is no work to which I feel so much personal indebtedness as to this of Werner's.

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Some wave functions for the four-electron threecentre bonding of four- and eight-π-electron systems

Australian Journal of Chemistry ◽

10.1071/ch9740691 ◽

1974 ◽

Vol 27 (4) ◽

pp. 691 ◽

Cited By ~ 33

Author(s):

RD Harcourt ◽

JF Sillitoe

Keyword(s):

Molecular Orbital ◽

Configuration Interaction ◽

Electron Pair ◽

Valence Bond ◽

Pair Bond ◽

Wave Functions ◽

Electron Systems ◽

Numerical Evidence ◽

The One ◽

Increased Valence

For symmetrical four-electron three-centre bonding units, the standard valence-bond (VB), delocalized molecular orbital (MO), increased-valence (IV) and non-paired spatial orbital (NPSO) representations of the electrons are Diagram O3, NO2- and CF2 with four π-electrons, and N3-, CO2 and NO2+ with eight π-electrons, have respectively one and two four-electron three-centre bonding units for these n-electrons. By means of Pople-Parr-Pariser type approximations, the MO, standard VB, IV and NPSO wave functions for these systems are compared with complete VB (or best configuration interaction) wave functions for the ground states. Similar studies are reported for the n-electrons of N2O. Further demonstration is given for the important result obtained elsewhere that the IV formulae must always have energies which are lower than those of the standard VB formulae, provided that the same technique is used to construct electron-pair bond wave functions. The extra stability arises because IV formulae summarize resonance between the standard VB formulae and long-bond formulae of the type Diagram As has been discussed elsewhere, the latter structure can make appreciable contributions to the complete VB resonance when its atomic formal charges are either zero or small in magnitude.If two-centre bond orbitals are used to construct the wave functions for the one-electron bond(s) and the two-electron bond(s) of IV formulae, then the IV and MO wave functions are almost identical for the symmetrical systems. Further numerical evidence is provided for this near-equivalence.

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