Interaction stabilization energies representation

Figure 11-4 Compare this picture of the formation of the tt bond in ethene with Figure 11 -3. in-phase interaction between two paraiiei p orbitais (containing one eiectron each shown in biue) resuits in positive overiap and a fiiied bonding tt orbital. The representation of this orbital indicates the probability of finding the electrons between the carbons above and below the molecular plane. Because rr overlap is less effective than o-, the stabilization energy, is smaller than tsE. The rr bond is therefore weaker than the o- bond. The out-of-phase interaction results in the antibonding molecular orbital tt. ...

Fig. 6. Representation of states for a hypothetical protein composed of two cooperative folding units. Free energy differences designated in uppercase letters represent the intrinsic stabilities of the cooperative units and have a contribution to the statistical weights designated by k. Free energy differences designated in lowercase letters represent the interaction between cooperative units and have a contribution to the statistical weights designated by . [Reprinted from Freire and Murphy (1991).]...

Fig. 20.2 Proportional representation of the intermolecular interaction energy components, calculated at the MP2/aug-cc-pVDZ level of theory, for stacked nucleic acid base complexes. Shown is the percentage contribution to the sum of all stabilizing terms...

The second contribution to the steric interaction arises from the loss of configurational entropy of the chains on significant overlap. This effect is referred to as entropic, volume restriction, or elastic interaction, Gei. The latter increases very sharply with a decrease in h when the latter is less than 8. A schematic representation of the variation of Gmix, Gei, G, and Gj =G X + Gei + Ga) is given in Fig. 10. The total energy-distance curve shows only one minimum, at h 25, the depth of which depends on 5, R, and A. At a given R and A, G decreases with an increase in 5. With small particles and thick adsorbed layers (5 > 5 nm), G, becomes very small (approaches thermodynamic stability. This shows the importance of steric stabilization in controlling the flocculation of emulsions and suspensions. 

The potential energies associated with various clay surface interactions can be combined to yield an extended-DLYO mathematical representation of the net particle stability... 

Life involves (1) a pattern in spacetime (rather than a specific material object) (2) self-reproduction, in itself or in a related organism (3) information-storage of a self-representation (4) metabolism that converts matter/energy (5) functional interactions with the environment (6) interdependence of parts within the organism (7) stability under perturbations of the environment and (8) the ability to evolve. 

Figure 8.3. Electrostatic stabilization of colloidal particles (a) schematic representation of the electrostatic interaction energy-distance curve for two approaching particles (not to scale) (b) calculated electrostatic interaction curves according to equations (8.20a-8.20c)...

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