Electron intermolecular

In NBO language, the resonance hybrid (5.29a) corresponds to a two-electron intermolecular donor-acceptor interaction of the form... 

The SCF-MI BSSE free method does not take into account dispersion forces, connected to electronic intermolecular correlation effects. By using the SCF-MI wave function as a starting point, however, a non orthogonal BSSE free Cl procedure can be developed. This approach was applied to compute intermolecular interactions in water dimer and trimer the resulting ab initio values were used to generate a new NCC-like potential (Niesar et al, 1990). Molecular dynamics simulation of liquid water were performed and satisfactory results obtained (Raimondi et al, 1997). 

The quantities (2.59) may be expressed using complementary assumptions. For instance, for purely electronic intermolecular interactions Jnm, we obtain the following relations ... 

The superconducting ability of [M(dmit)2] complexes, see Fig. 9, has prompted experimental and theoretical vibrational studies of [Ni(dmit)2]z and [Pd(dmit)2]z complexes (z is in the range 0-2—), in order to understand the mechanism of superconductivity in terms of electron-intramolecular and electron-intermolecular vibrational couplings (14, 21). These studies have... 

This mechanism with coupled one-electron intermolecular electron transfer from the external donor and intramolecular multi-electron transfer from the catalyst to coordinated N2 is, presumably, more efficient than the simpler mechanism considered above with one-electron and multi-electron transfers separated in time. In this mechanism the strongest reductant, which is of necessity the external reducing agent, is used for direct reduction of the substrate, whereas for consecutive one-electron and multi-electron processes its reducing power is used only to prepare the reduced form of the catalyst. 

The redox behavior of the F and H centers in hydrogenases I and II is nicely consistent with their respective modes of function. As shown in Figure 7.22, the F clusters are presumed to transfer electrons intermolecularly with the exter-... 

If chromophores are treated as point dipoles (this amounts to neglecting the effect of nuclear repulsive interactions, i.e., size and shape of the chromophore), an analytical expression can be readily derived [59— 67] that illustrates that electronic intermolecular electrostatic interactions contribute an attenuation factor to the order parameter expression namely (cos 0) = /u,f/5fcT[l — (W/kT)] where L is the... 

Wang 0, Akhremitchev B and Walker G 0 1997 Femtosecond infrared and visible spectroscopy of photoinduced intermolecular electron transfer dynamics and solvent-solute reaction geometries Coumarin 337 in dimethylaniline J. Rhys. Chem. A 101 2735-8... 

Induced dipole/induced dipole forces are the only intermolecular attractive forces available to nonpolar molecules such as alkanes In addition to these forces polar molecules engage m dipole-dipole and dipole/mduced dipole attractions The dipole-dipole attractive force is easiest to visualize and is illustrated m Figure 4 3 Two molecules of a polar substance experience a mutual attraction between the positively polarized region of one molecule and the negatively polarized region of the other As its name implies the dipole/induced dipole force combines features of both the induced dipole/mduced dipole and dipole-dipole attractive forces A polar region of one mole cule alters the electron distribution m a nonpolar region of another m a direction that produces an attractive force between them... 

The next important phenomena that the result of supramolecular effect are the concentration and proximity effects concerning the components of analytical reaction, even through they are considerably different in hydrophobicity, charge of the species, complexing or collisional type of interaction. The concentration and proximity effects determine the equilibrium of analytical reaction, the efficiencies of intramolecular or intermolecular electronic energy or electron transfer and as a result the sensitivity of analytical reactions. 

For aromatic hydrocarbon molecules, in particular, the main acceptor modes are strongly anharmonic C-H vibrations which pick up the main part of the electronic energy in ST conversion. Inactive modes are stretching and bending vibrations of the carbon skeleton. The value of Pf provided by these intramolecular vibrations is so large that they act practically as a continuous bath even without intermolecular vibrations. This is confirmed by the similarity of RLT rates for isolated molecules and the same molecules imbedded in crystals. 

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