Electronegativity, acids, and bases. IV. Concerning the inductive effect of alkyl groups

Huheey, James E.

doi:10.1021/jo00800a044

Cited by 89 publications

(64 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The coefficient b is related inversely to a second important atomic property, the charge-carrying capacity j. This property, first emphasized by Huheey [6], reflects the ability of the atom to absorb or release additional charge. For example, although fluorine has the highest electronegativity in the halogen group, it has a lower ability than the other halogens to accommodate additional charge.…”

Section: Introductionmentioning

confidence: 99%

Charge competition in halogenated hydrocarbons

Gross¹,

Hadad²,

Seybold³

2011

Int J of Quantum Chemistry

View full text Add to dashboard Cite

ABSTRACT:The distribution of electronic charge in a molecule plays a major role in determining the molecule's physical, chemical, and biological properties. For studies of charge distributions, halogenated hydrocarbons are especially informative prototype systems, because the overall charge distributions depend strongly on both the identities and relative positions of the halogen substituents. In this report, we examine how the placement and identities of the halogen substituents affect the natural population analysis, atoms in molecules, and Gasteiger partial atomic charge distributions in representative saturated (methanes and ethanes), unsaturated (ethylenes), and aromatic (benzenes) halogenated hydrocarbons, using density functional calculations. The results are interpreted in terms of the electronegativities and the charge capacities of the halogens. The relationships of these charge distributions to the electrostatic potential maps of the compounds are also explored.

show abstract

Section: Introductionmentioning

confidence: 99%

Charge competition in halogenated hydrocarbons

Gross¹,

Hadad²,

Seybold³

2011

Int J of Quantum Chemistry

View full text Add to dashboard Cite

show abstract

“…In this article we shall be concerned only with its magnitude. α is a measure of how readily the charge distribution can undergo rearrangement, and thus is closely related to such key chemical reactivity concepts as hardness, softness, and charge capacity 3–12, as well as to thermodynamic stability 13–18. Indeed, the maximum hardness principle 19–24, according to which “there seems to be a rule of nature that molecules arrange themselves so as to be as hard as possible” 19, has a counterpart in the minimum polarizability principle 14–18, which states that “the natural direction of evolution of any system is toward a state of minimum polarizability” 14.…”

Section: Introductionmentioning

confidence: 99%

Local ionization energy and local polarizability

Jin

Murray

Politzer

2003

Int J of Quantum Chemistry

View full text Add to dashboard Cite

ABSTRACT:We investigate relationships between molecular polarizability ␣, volume V, ionization energy I, and average local ionization energy I (r ៝). The last of these is a measure of the energy required to remove an electron from any point r ៝ in the space of an atom or molecule. Molecular polarizability shows a good direct correlation with volume, which can be improved to a minor extent by including an inverse dependence on I and more so by using I (r ៝) averaged over the surface of the molecule, I S,ave . The pattern of I (r ជ) on a molecular surface, I S (r ៝), exhibits significant variability, and it is shown through a series of examples that this can be related to the electronic structure of the molecule and to local polarizability. Thus, I S (r ៝) will provide a means of assessing the transferability of regional (e.g., group/bond) polarizabilities from one molecule to another.

show abstract

“…A number of examples of this have been observed and discussed [13][14][15][16][19][20][21][22][23][24]. For instance, in a recent computational study of the electrostatic potentials associated with naphthalene derivatives, we found evidence that the electron-attracting tendencies of the halogens in 1-halonaphthalenes increase in the order F < Br < CI [24].…”

Section: 'R -I -A (5)mentioning

confidence: 78%

“…When the expansion in Eq. (1) is truncated after the second term, it is similar in form to an electronegativity expression given by Huheey 1,[13][14][15][16], following upon earlier work by others [17,18]:…”

Section: Charge Capacitymentioning

confidence: 99%

“…It means that an atom (or group) with a large value of ~ may be more negative, in a given molecule, than another that has a greater electronegativity, and thus a stronger initial attraction for electronic charge, but is not able to accommodate as much of it. The recognition of this has made it possible to explain a considerable variety of observations, many of which seem to be anomalous or contradictory [13][14][15][16][19][20][21][22][23][24].…”

Section: Charge Capacitymentioning

confidence: 99%

See 1 more Smart Citation

Charge capacities and shell structures of atoms

View full text Add to dashboard Cite

This paper focuses upon two important features of atoms: their charge capacities and their shell structures. The charge capacity ~c is a measure of an atom's ability to accommodate a gain or loss of electronic charge in the process of forming a molecule. Estimated values of ~: are presented for the atoms Li-Xe. The overall trend is that as the inherent (neutral atom) electronegativity increases, decreases. The shell structure of an atom can be discerned by plotting its local ionization energy ](r) against radial distance from the nucleus; it decreases in a roughly stepwise manner and the inflection points correspond to meaningful boundaries between the electron shells. An effective "outer radius" rs for an atom can be defined in terms of the sphere that encompasses all but 0.2 of its electrons. For nearly three-fourths of the atoms, the outer shell is found to be 97% or more of the total volume. The computed populations, radii and volumes of all of the shells are presented for the atoms Li-Xe, as well as the magnitudes of i(r) at all shell boundaries. Good correlations exist between atomic polarizability, I(rs), ~ and outer shell electron density. It is suggested that ](r) can be used as a measure of local polarizability, c~(r), in atoms and molecules.

show abstract

Electronegativity, acids, and bases. IV. Concerning the inductive effect of alkyl groups

Cited by 89 publications

References 1 publication

Charge competition in halogenated hydrocarbons

Charge competition in halogenated hydrocarbons

Local ionization energy and local polarizability

Charge capacities and shell structures of atoms

Contact Info

Product

Resources

About