Overlap, effect

Kreek H and Meath W J 1969 Charge-overlap effects. Dispersion and induction forces J. Chem. Phys. 50 2289... 

Koide A, Meath W J and Allnatt A R 1981 Second-order charge overlap effects and damping functions for isotropic atomic and molecular interactions Chem. Phys. 58 105... 

As will be discussed in detail here, these herbs may create several effects, due to multiple neuropharmacological actions or even due to a single action. For the sake of convenience, the herbs have been broadly classified here into antidepressant/anxiolytic and antipsychotic categories due to their frequently overlapping effects. 

Ce/r j, overestimates the SAPT values calculated 10 for the H H system by 2.8 times at r = 4ao and by 1.6 times at r = Sag. For the H3 trimer, in the equilateral triangle structure with sides equal to 5oo, the Axihrod-Teller energy is more than two times larger than in calculations taking into account the overlap effect . The damping functions have to improve the behavior of dispersion terms at intermediate and short distances. 

This expression has seen many developments through the years and has evolved into the so-called London-Eyring-Polanyi-Sato (LEPS) surface in which expression (30) is multiplied by an empirical factor (1 + k)" which is supposed to take account of overlap effects (90). The coulomb and exchange integrals are calculated from the singlet and triplet potential curves of the diatomics, given by the expressions... 

We have seen above that the pairwise-additive parts of the ternary induced dipole component are well known for a number of systems. The irreducible, ternary components, on the other hand, are poorly known, for any system. Even less is known about the N-body irreducible components of the induced dipole for N > 3. Attempts exist to model three- and four-body dipole components on the basis of classical relationships, but the evidence indicates that overlap effects are important the known many-body dipole models do in general not account for quantum effects. 

The C—Cl bond is so long that the lone-pair orbital (3p) of chlorine is too far away to overlap effectively with the it orbital of the carbonyl group. The carbonyl group of an acyl chloride feels the normal electron-withdrawing effect of an electronegative substituent without much compensating electron donation by resonance. This destabilizes the carbonyl group and makes it more reactive. 

Using the double bonds, we conclude that the twisted configuration shown in Figure 6-17 should not be very stable. Here the p orbitals are not in position to overlap effectively in the tt manner. The favored configuration is expected to have the axes of the p-tt orbitals parallel. Because considerable energy would have to be expended to break the p-tr double bond and to permit rotation about the remaining sp2-cr bond, restricted rotation and stable cis-trans isomers are expected. Similar conclusions can be reached on the basis of the r model of the double bond. 

FIGURE 14.2 (a) The p-orbitals of Period 3 and heavier elements are held apart hy the cores of the atoms (shown in gray) and have very little overlap with each other, (b) In contrast, the atoms of elements in Period 2 are small and can overlap effectively with each other and with elements in later periods. 

A comparison between equations (7.8)-(7.9) and (7.12)-(7.13) shows that the exponential terms in Eqs. (7.12) and (7.13) represent the overlap effect (overlap correction). This new model of simultaneous nucleation and growth of nuclei, Eqs. 

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