Entropic characteristic temperature

From the limits of Eq. (1.86) one observes the major role the topological index plays in predicting the characteristic temperature T = 2E/k at which a given nanosystems (topology) is stabilized (either as ideal or with defects) by the bondonic motion through it otherwise, for an absent topology the bondonic motion is purely entropic at T = OK, without observable character, according with Eq. (1.86) for the indefinite limit — oo x o. 

If we now assume that this surface at temperature T is in equilibrium with a gas then the adsorption rate equals the desorption rate. Since the atoms/molecules are physisorbed in a weak adsorption potential there are no barriers and the sticking coefficient (the probability that a molecule adsorbs) is unity. This is not entirely consistent since there is an entropic barrier to direct adsorption on a specific site from the gas phase. Nevertheless, a lower sticking probability does not change the overall characteristics of the model. Hence, at equilibrium we have... 

A characteristic feature of sterically stabilized systems is their different responses to temperature change. Those in (i) flocculate on cooling, while for (ii) flocculation occurs on heating, and for (iii) there is no accessible (critical) temperature for flocculation. Entropic stabilization seems to be more common in non-aqueous media, whereas enthalpic stabilization is more frequently encountered in aqueous media. Examples of the three types of stabilization were given by Napper. ... 

The Brownian motion of a polymer chain for self-diffusion is carried out by the integration of Brownian motions of monomers. Therefore, the entropic elasticity of chain conformation in a random coil allows a large-scale deformation, with its extent subject to the external stress for polymer deformatiOTi and flow, and hence exposes the characteristic feature of a mbber state in a temperature window between the glass state and the fluid state. 

It is important to understand that chromatographic separations cannot be exclusively energetically driven or entropically driven both components will always be present to a greater or lesser extent. It is by the careful adjustment of both the energetic and entropic components of a distribution that very difficult and subtle separations can be accomplished. For both systems, there is characteristic plus value of the slope, which means that the process of molecule transfer between the stationary and mobile phase has negative value of change of enthalpy and the heat energy is released. Then it is clear that, in this case, the increase of the temperature is responsible for a decrease in retention and usually in enantioselectivity as well. 

The result implies that a sequence behaves like a spring, showing a linear relation between force and extension. The force constant is proportional to the absolute temperature T, as is characteristic for forces of entropic origin. Note furthermore that 6r decreases on increasing the size of the sequence. 

Indeed, a strict proportionality to the absolute temperature is the characteristic signature for all forces of entropic origin. Just remember the ideal gas which is probably the better known system, where we find p T. 

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