Gibbs free energy of association

The goal of the study was to measure the strength of an NH-tt interaction (the "attractive" interaction in complex A). Comparing the Gibbs free energy of association of complex A and B could give an estimate of its strength. 

From basic physical chemistry we know that the Gibbs (free) energy of association AGa, of a ligand X interacting with a receptor Y with an association constant, AT a is given by... 

The basic criterion for equilibrium with respect to a given chemical reaction is that the Gibbs free energy change associated with the progress of the reaction be zero. 

The excess thermodynamic properties correlated with phase transitions are conveniently described in terms of a macroscopic order parameter Q. Formal relations between Q and the excess thermodynamic properties associated with a transition are conveniently derived by expanding the Gibbs free energy of transition in terms of a Landau potential ... 

Order parameters may also refer to underlying atomic structure or symmetry. For example, a piezoelectric material cannot have a symmetry that includes an inversion center. To model piezoelectric phase transitions, an order parameter, r], could be associated with the displacement of an atom in a fixed direction away from a crystalline inversion center. Below the transition temperature Tc, the molar Gibbs free energy of a crystal can be modeled as a Landau expansion in even powers of r (because negative and positive displacements, 77, must have the same contribution to molar energy) with coefficients that are functions of fixed temperature and pressure,... 

Af/a(is enthalpy of adsorption, A ads entropy change associated with the adsorption of the protein onto the surface, AGads Gibbs free energy of adsorption... 

Fig. 9. Calculated overall free energy of stabilization (AGtota ) for yeast phos-phoglycerate kinase at pH 6.5 and 0.7 M GuHCl. This curve displays two zeros, corresponding to the temperatures of cold and heat denaturation. Also shown in the curve are the cooperative Gibbs free energies (AG ) associated with the uncompensated exposure of apolar surfaces on unfolding of each of the domains. For both domains, AG is positive for the heat denaturation and close to zero for the cold denaturation. This behavior results in a cooperative heat denaturation and a non-cooperative cold denaturation. [Reprinted from Freire el al. (1991).]...

Figure 5 Thermodynamic parameters associated with organohaUde reactivity (a) electon accepting species versus redox potential (b) relative importance of oxidation versus dechlorination rates as a function of number of chlorines [1-8] and (c) trend between energy difference of the HOMO and LUMO electron layers and Gibbs free energy of...

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