Electrostatic potential, for

If you calculate the electrostatic potential for cyclopropane, three minima occur in regions that bisect the carbon-carbon bonds. This result IS consistent with protonalion of cyclopropane occurring along Ih e bond bisector. 

The classical electrostatic potential for q point charges is the potential energy at a position R (equation 18). 

Nucleophiles can also act as acids and bases, and this behavior substantially alters their nucleophilicity. At pH 5, trimethylamine exists mainly as its conjugate acid, trimethylammonium cation. First draw a Lewis structure, and then examine the electrostatic potential for trimethylammonium ion. On the basis of the map, which is the better nucleophile, the cation or the corresponding neutral amine At pH 12, phenol exists mainly as its conjugate base, phenoxide anion. First draw a Lewis structure (or series of Lewis structures), and then examine the electrostatic potential map for phenoxide anion. Which is the better nucleophile, phenoxide or phenol ... 

Carrupt, P. A., El Tayar, N., Karlen, A., Testa, B. Value and limits of molecular electrostatic potentials for characterizing drug-biosystem interactions. Methods Enzymol. 1991, 203, 638-677. 

P.-A. Carrupt, N. El Tayar, A. Karlen, and B. Testa, Molecular Electrostatic Potential for Characterizing Drug-Biosystem Interactions, Academic Press, London, 1991, pp. 638-677. 

Streitz FH, Mintmire JW (1994) Electrostatic potentials for metal-oxide surfaces and interfaces. Phys Rev B 50(16) 11996-12003... 

Figures 3.1 and 3.2 show calculated electrostatic potentials for guanine (1), in the plane of the molecule and on the molecular surface, respectively. Looking at Figures 3.1 and 3,2, it can be seen that there are negative potentials associated with N3, N7 and the carbonyl oxygen, with the latter two overlapping to form a strong and extensive negative region on one side of the molecule. Both Figs. 3.1 and 3.2 allow us to rank N as the site most suscepti-...

Bonaccorsi, R., A. Pullman, E. Scrocco, and J. Tomasi. 1972b. The Molecular Electrostatic Potentials for the Nucleic Acid Bases Adenine, Thymine and Cytosine. Theor. Chim. Acta 24, 51. 

J. Li, C. J. Cramer, and D. G. Truhlar, A two-response-time model based on CM2/INDO/S2 electrostatic potentials for the dielectric polarization component of solvatochromic shifts on vertical excitation energies, Int. J. Quan. Chem. 77 264 (2000). 

Fig. 8.1 Calculated electrostatic potential for aniline (1), in kcal -mol-1, in (a) the plane containing the aromatic ring and amine nitrogen, (b) the plane 1.5 A above the aromatic ring (on the side with the nitrogen lone pair), and (c) the plane perpendicular to the aromatic ring and slicing through the C-N bond and the para carbon. The nuclear positions or their pro-...

Figure 17.6 Distribution of the electrostatic potential for an ensemble of hard sphere ions and dipoles in contact with a hard wall the straight line is the prediction of the Gouy-Chapman theory. Data taken from Ref. 8.

Predicted ionic radii r, experimental ionic radii n, central charge Q and RF potential Ok in atomic units. Electrostatic free energies of solvation, 8pel, in kcal/mol. Experimental values from reference [16]. Electrostatic potential for anions from reference [19]. For all calculations done, the effective dielectric constant reported in [16] was used. 

The use of electrostatic potentials, defined in the context of DFT, for the calculation of ion solvation energies has been reviewed. It has been shown that physically meaningful ionic radii may be obtained from this methodology. In spite of the fact that the electrostatic potentials for cations and anions display a quite different functional dependence with the radial variable, we have shown that it is still possible in both cases to build up a procedure consistent with the Bom model of ion solvation. 

Because the Coulomb potential plays a central role in the model outlined above, it seems important to examine the full electrostatic potential experienced by an electron as it approaches the C-S bond region. In Fig. 10 we show the electrostatic potential for Me-S-Me molecule in the absence of any positive charges, with blue denoting attractive regions and red labeling repulsive regions. 

The methods developed from either NN or IT undoubtedly reduce the requirements concerning the hardware that must be applied. In the NN approach it is sufficient to determine electrostatic potential, for which far less computer resources are required than for solving HFR equations supplemented with the energy of correlations, necessary for reliable calculation of interaction energy. Similarly, the calculation of information entropy (the IT case) based on the electron density is possible, and can be done with much shorter calculation time than in the case of HFR equations with the correlation energy. 

Fluorine substitution has greatly diminished the (negative) electrostatic potential for the internal double bond, but has had little effect on the potential for the external double bond. The change in selectivity (toward favoring addition onto the external double bond) is a direct consequence given that carbene addition is electrophilic addition. 

A field is a function that describes a physical property at points in space. In a scalar field, this physical property is completely described by a single value for each point (e.g. temperature, density, electrostatic potential). For vector fields, both a direction and a magnitude are required for each point (e.g. gravitation,... 

As mentioned earlier, the existence of surface shifted core levels has been questioned.6 Calculated results for TiC(lOO) using the full potential linearized augmented plane wave method (FLAPW) predicted6 no surface core level shift in the C Is level but a surface shift of about +0.05 eV for the Tis levels. The absence of a shift in the C Is level was attributed to a similar electrostatic potential for the surface and bulk atoms in TiC. The same result was predicted for TiN because its ionicity is close to that of TiC. This cast doubts on earlier interpretations of the surface states observed on the (100) surface of TiN and ZrN which were thought to be Tamm states (see references given in Reference 4), i.e. states pulled out of the bulk band by a shift in the surface layer potential. High resolution core level studies could possibly resolve this issue, since the presence of surface shifted C Is and N Is levels could imply an overall electrostatic shift in the surface potential, as suggested for the formation of the surface states. 

Here (p is the inner electrostatic potential of the bulk, % is the dipole surface potential, and t f is the outer electrostatic potential. For y/ 0, the work function consists... 

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