Perturbation, of electrons

To first order, the dispersion (a-a) interaction is independent of the structure in a condensed medium and should be approximately pairwise additive. Qualitatively, this is because the dispersion interaction results from a small perturbation of electronic motions so that many such perturbations can add without serious mutual interaction. Because of this simplification and its ubiquity in colloid and surface science, dispersion forces have received the most significant attention in the past half-century. The way dispersion forces lead to long-range interactions is discussed in Section VI-3 below. Before we present this discussion, it is useful to recast the key equations in cgs/esu units and SI units in Tables VI-2 and VI-3. 

The source of free radicals is multiplied under these circumstances, arachidonic acid metabolism, activation of xanthine oxidase, perturbation of electron flow within the respiratory chain, and NOS activation. Structurally, excitotoxicity is generally described as a necrotic process involving initial swelling of the cell and of the endoplasmic reticulum, clumping of chromatin, followed by swelling of the... 

These considerations clearly suggest that kinetic stabilization is a far better way to stabilize the triplet states of carbenes than thermodynamic stabilization. It is also important to note that thermodynamic stabilization usually results in the perturbation of electronic integrity of the reactive center, as has been seen in the case of phosphinocarbene and imidazol-2-ylidene (112). " On the other hand,... 

The perturbation of electron states by the pseudopotential modifies the total energy by a term called the band-structure energy, which is obtained to second order in the pseudopotential it is essential to an understanding of the bonding properties, and it can be directly evaluated for any specified positions of the metallic ions. It may also be thought of as contributing to an effective interaction between ions the interaction shows Friedel oscillations at large separations. 

Depending on the nature of the metal (M), the initial metal chloride (MC1 ) or a product MClj j,(OR)j, forms an addition complex with alcohol molecules (ROH) without enough perturbation of electronic charges for the reaction to proceed further. The reactions of metal tetrachlorides MCU (M = Ti, Zr, Th) towards ethyl alcohol show a gradation TiCU > Z1CI4 > ThCLj. ... 

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