Berechnung von freien Hydratationsenthalpien und Koordinationszahlen für Kationen aus leicht zugänglichen Parametern

Morf, Werner E.; Simon, W.

doi:10.1002/hlca.19710540304

Cited by 67 publications

(11 citation statements)

References 34 publications

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“…The interactions of metal ions in general with nucleic acids are governed by complex stabilities according to the Irving-Williams series [65] and Martin's Stability Ruler [66,67], by the relative affinities for oxygen versus nitrogen ligands [8] and by first shell hydration enthalpies (Table 2) [10,[68][69][70][71][72][73][74][75][76][77][78]. Ca 2+ , for example, shares the preference of Mg 2+ for phosphate oxygen ligands, but is larger in size and thus compatible with higher coordination numbers and a more loose packing of ligands.…”

Section: Influences Of Metal Ions Other Than Mgmentioning

confidence: 99%

Characterization of Metal Ion-Nucleic Acid Interactions in Solution

Pechlaner

Sigel

2011

Metal Ions in Life Sciences

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Metal ions are inextricably involved with nucleic acids due to their polyanionic nature. In order to understand the structure and function of RNAs and DNAs, one needs to have detailed pictures on the structural, thermodynamic, and kinetic properties of metal ion interactions with these biomacromolecules. In this review we first compile the physicochemical properties of metal ions found and used in combination with nucleic acids in solution. The main part then describes the various methods developed over the past decades to investigate metal ion binding by nucleic acids in solution. This includes for example hydrolytic and radical cleavage experiments, mutational approaches, as well as kinetic isotope effects. In addition, spectroscopic techniques like EPR, lanthanide(III) luminescence, IR and Raman as well as various NMR methods are summarized. Aside from gaining knowledge about the thermodynamic properties on the metal ion-nucleic acid interactions, especially NMR can be used to extract information on the kinetics of ligand exchange rates of the metal ions applied. The final section deals with the influence of anions, buffers, and the solvent permittivity on the binding equilibria between metal ions and nucleic acids. Little is known on some of these aspects, but it is clear that these three factors have a large influence on the interaction between metal ions and nucleic acids.

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Section: Influences Of Metal Ions Other Than Mgmentioning

confidence: 99%

Characterization of Metal Ion-Nucleic Acid Interactions in Solution

Pechlaner

Sigel

2011

Metal Ions in Life Sciences

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“…8.2 and 10.0 eV) therefore exhibit a double maximum for normal dispersion and a double minimum for anomalous dispersion (12 extrema between 7.2 and 10.4 …”

Section: Security Classification Of This Page (Wheu Datementioning

confidence: 99%

Nonequilibrium electronic polarization of the solvent in photoionization

Delahay¹,

Dziedzic²

1986

The Journal of Chemical Physics

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The energetics of photoionization in condensed phases includes a significant contribution from nonequilibrium processes arising from dielectric dispersion of the solvent at the prevailing photon energy. The solvent is polarized by the varying electric field caused by the change of ionic valence as a result of photoionization. This ionic field varies in a time interval determined by the frequency of incident radiation. The following contributions from nonequilibrium processes to the energetics of photoionization are calculated for transparent and absorbing solvents: electronic polarization, London dispersion, and Born repulsion energies for a discrete model of coordinated solvent molecules in the inner-sphere solvation shell of anions and cations; electronic polarization of the outer-sphere region for a continuous medium model. The losses resulting from the rapid variation of the ionic field for an absorbing solvent are calculated for the inner- and outer-sphere regions, respectively, from a discrete model and a continuous medium. Damping of the ionic field resulting from solvent absorption is negligible. The theory is applied to aqueous solutions in the 7–10.4 eV range of photon energies by using dielectric data from reflectance spectroscopy of liquid water. Experimental dispersion spectra for photoelectron emission have the shape predicted by theory and display all the extrema at the photon energies of the calculated curves. The very pronounced effect of ionic strength on the balance between inner- and outer-sphere contributions predicted by theory (inner–outer sphere splitting) is fully confirmed by experiment. Dispersion spectra of inorganic ions in the range of each of the two absorption bands of liquid water (maxima at ∼8.2 and 10.0 eV) therefore exhibit a double maximum for normal dispersion and a double minimum for anomalous dispersion (12 extrema between 7.2 and 10.4 eV). Specific effect of the nature of anions is evident above 9.0 eV in inner–outer sphere splitting. The present study provides a way of probing the response of liquids and solutions to the rapidly varying intense ionic field resulting from the process of photoionization.

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“…The expression for U (nucl) is taken from [2] with the additional consideration of the difference in water orientation around anions and cations. By analogy with [2], one writes Combining eqs.…”

Section: Energy Of Inner-sphere Reorganization Of Anionsmentioning

confidence: 99%

“…A negative sign is assigned to the right-hand-side of eq. (14) in the present treatment since the initial state corresponds to the solvated ionic species and thus differs from that of [2]. Data on these volumes are given in [8].…”

Section: Sf -6ufmentioning

confidence: 99%