D

Buckingham, J.

doi:10.1007/978-1-4899-6850-0_4

Cited by 3 publications

(5 citation statements)

References 379 publications

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“…For example, the occupancy of σ* OH is 0.028 electron in the complex with veratrole, while it is 0.031 electron with anisole. This testifies again to the pre-eminence of the electrostatic over the charge transfer in the hydrogen-bond energy …”

Section: Resultsmentioning

confidence: 76%

“…Two simple descriptors of the base, however, give better affinity orders than electronegativity and hardness, namely the ionization energy difference Δ IE as defined by Allen (the difference between the energy ionizations of the base and the noble gas atom in its row) and the minimum electrostatic potential V S,min of the base (situated on E in the direction of a putative lone pair). The correlation with Δ IE ( r = 0.911) expresses the contributions of dispersion, induction, and charge transfer to the hydrogen-bond energy, while the correlation with V S,min ( r = 0.868) expresses the well-known importance of the electrostatic term . The values of the parameters χ, η, Δ IE , and V S,min and figures illustrating the correlations are given in the Supporting Information.…”

Section: Resultsmentioning

confidence: 99%

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An Enthalpic Scale of Hydrogen-Bond Basicity. 4. Carbon π Bases, Oxygen Bases, and Miscellaneous Second-Row, Third-Row, and Fourth-Row Bases and a Survey of the 4-Fluorophenol Affinity Scale

et al. 2010

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The thermodynamics of the O-H...B hydrogen bond (HB) has been determined in CCl(4) by FTIR spectrometry for a wide variety of carbon pi bases, oxygen bases, and miscellaneous first- to fourth-row bases, using 4-fluorophenol as a reference hydrogen-bond donor (HBD). After inclusion of previously studied nitrogen, sulfur, and halogen bases, this 4-fluorophenol affinity scale contains 314 varied organic bases and ranges over 40 kJ mol(-1). The 4-fluorophenol affinity scale in CCl(4) is shown to be applicable to most HBDs in most media, provided a small family dependence is taken into account. The HB affinity orders are quantitatively established according to the atomic acceptor site or to its bearing functional group. A comprehensive survey of the influence of substituents on these affinity orders is then achieved, considering electronic and steric effects, as well as effects of vinylogy or iminology. Iminology is found to be more efficient than vinylogy for transmitting resonance effects. Steric effects are shown to be less important in HB affinity than in HB basicity since they mainly act on the HB entropy. The spatial proximity of two acceptor sites can favor complexation through three-center hydrogen bonds, leading to superhydrogen-bond bases on the affinity scale.

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Section: Resultsmentioning

confidence: 76%

Section: Resultsmentioning

confidence: 99%

An Enthalpic Scale of Hydrogen-Bond Basicity. 4. Carbon π Bases, Oxygen Bases, and Miscellaneous Second-Row, Third-Row, and Fourth-Row Bases and a Survey of the 4-Fluorophenol Affinity Scale

et al. 2010

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“…Hydrogen bonding (HB) is an extensively researched topic in chemistry and biology because of its ubiquitous influence on a myriad of chemical and biological systems. , Nonetheless, the nature of hydrogen bonding still represents an intriguing issue in charged complexes and systems consisting of ions because its classification appears to be rather difficult. Hydrogen bonding is normally referred to as a mainly electrostatic interaction, whereas its dispersion character arising from electron correlation effects cannot be neglected.…”

Section: Introductionmentioning

confidence: 99%

“…The interplay among these three forces also determines the nature of hydrogen bonding. It is obvious that the Coulomb and induction interactions dominate the system, for which the dipole moments of the bonds involved are non-negligible . For example, in the water dimer, (H 2 O) 2 , the Coulomb attraction contributes >50% to the final interaction energy .…”

Section: Introductionmentioning

confidence: 99%

Nature of Hydrogen Bonding in Charged Hydrogen-Bonded Complexes and Imidazolium-Based Ionic Liquids

2011

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The nature of hydrogen bonding was compared in neutral complexes and negatively charged complexes consisting of either the HF molecule or the halide anion (fluoride and chloride) and the C-H bond in the methane molecule with a varying degree of fluorination (such as CH(4), CH(2)F(2), and CHF(3)). Both linear (C(3v) symmetry) and nonlinear (C(2v) symmetry) hydrogen-bonded complexes were studied. Symmetry-adapted perturbation theory was used to decompose interaction energies into fundamental components such as Coulomb, repulsion, induction and dispersion to analyze the interplay among these forces in stabilizing hydrogen bonding. In the linear charged complexes, both Coulomb attraction and induction significantly contributed to the stabilization of hydrogen bonding. In the nonlinear charged complexes, mainly Coulomb attraction contributed to the HB complex stabilization, with the inductive forces playing a less important role. Contrary to the neutral complexes, dispersion forces played only a marginal role in the charged complexes. Interplay between the fundamental forces was also investigated in the ion pairs of the imidazolium-based ionic liquid, [C(2)mim]Cl, that were categorized as either (1) typical ion-ion interaction, with the anion interacting from above or below the imidazolium plane; or (2) hydrogen-bonding interaction, with the anion interacting with the C2-H bond of the imidazolium cation. Both types of interactions were found to induce similar charge transfers, and the analysis of the energetic components revealed only a slight difference in the ion pairs studied: (1) both interactions were electrostatically driven, between 86% and 88% of the overall attractive energy, with the electrostatic component being slightly lower in the hydrogen-bonded ion pairs by ~8 kJ mol(-1); and (2) dispersion forces were found to be stronger in the typical ion-ion interactions by ~15 kJ mol(-1) and could be possible only due to the fact that the anion was able to move closer to the cation with no steric hindrance. From the experimental point of view, a vibrational red shift is expected in the hydrogen-bonded complexes of imidazolium-based ionic liquids, whereas the ion-ion interactions are more likely to produce a slight blue shift.

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“…Obviously, when the sphere is placed in an evanescent field, this approximation may not hold anymore. We can refine the description of the particle with a multipole expansion of the polarizability, 8 but we must then have clear indications as to how to restrict the required multipole expansion in order to describe efficiently the polarizability of the sphere. We shall show that the importance of terms higher than the dipole in the multipole expansion depends on the radius of the sphere and on its dielectric function.…”

Section: Introductionmentioning

confidence: 99%

Evanescent light scattering: The validity of the dipole approximation

et al. 1998

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In near-field optics the very concept of dipole is often used to represent either an elementary source or a scattering center. The most simple and widely used example is that of a small spherical particle whose polarizability is assumed to conform to the Clausius-Mossotti relation. While in conventional, far-field optics this approximation is known to be valid provided that the object is much smaller than the wavelength, its extension to near-field optics requires some precautions. Indeed, in the case of the scattering, by a spherical object, of an evanescent field generated, for instance, by total internal reflection or by a surface polariton, the strong-field gradient may increase the contribution to the polarizability of multipoles higher than the dipole. Such high-order multipoles are seldom considered in near-field optics because they complicate considerably any scattering calculation. In this paper we derive, for a spherical particle, the contributions of multipole orders up to the hexadecapole. This serves to illustrate the relative importance of each order. Moreover, within the framework of the coupled dipole method, we study, self-consistently, the problem of the scattering of an evanescent field by the sphere. We show that, with an initial field decreasing exponentially, the dipole approximation can be misleading.

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D

Cited by 3 publications

References 379 publications

An Enthalpic Scale of Hydrogen-Bond Basicity. 4. Carbon π Bases, Oxygen Bases, and Miscellaneous Second-Row, Third-Row, and Fourth-Row Bases and a Survey of the 4-Fluorophenol Affinity Scale

An Enthalpic Scale of Hydrogen-Bond Basicity. 4. Carbon π Bases, Oxygen Bases, and Miscellaneous Second-Row, Third-Row, and Fourth-Row Bases and a Survey of the 4-Fluorophenol Affinity Scale

Nature of Hydrogen Bonding in Charged Hydrogen-Bonded Complexes and Imidazolium-Based Ionic Liquids

Evanescent light scattering: The validity of the dipole approximation

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