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Free energy defined

Figure 3.8 Plots of the heights of the steps in Fig. 3.5 divided by the electron charge in order to get a potential. Via the relations in Fig. 3.7, these steps are all functions ofFo - On the vertical axis is the highest potential at which a step in the ORR is downhill in ftee energy, depicted as a function of the binding of O. The step that first becomes uphill in free energy defines (AEq)U. Steps 1 and 4 (lines labeled AGi and AG4, respectively) define the lower volcano and thereby t/oS (AFo)- Pt is the pure metal closest to the top. Figure 3.8 Plots of the heights of the steps in Fig. 3.5 divided by the electron charge in order to get a potential. Via the relations in Fig. 3.7, these steps are all functions ofFo - On the vertical axis is the highest potential at which a step in the ORR is downhill in ftee energy, depicted as a function of the binding of O. The step that first becomes uphill in free energy defines (AEq)U. Steps 1 and 4 (lines labeled AGi and AG4, respectively) define the lower volcano and thereby t/oS (AFo)- Pt is the pure metal closest to the top.
The key to understanding reaction equilibrium is the Gibbs free energy, ox free energy, defined as1-4 ... [Pg.97]

However, from the practical standpoint it appears expedient to use the so-called free energy which, in contrast to entropy, is amenable to measurement in the course of a reaction. The free energy defines a portion of the total energy of a system that can be converted to work at pressure and temperature kept constant. The free energy is... [Pg.173]

The change in Gibbs s free energy (defined, as stated, for a system at constant pressure and temperature) when a moles of A and b moles of B are converted into c moles of C and d moles of D is AG = cpc +dpD - apA - bpB, where p represent chemical potentials , i.e. free energy per mole of the substances, defined in terms of concentration of a component X as... [Pg.122]

Free energy defined as G = H — TS changes in G are a measure of the useful work that can be done by a system. [Pg.393]

In search of a criterion for spontaneity, Gibbs proposed a new function called the free energy, defined by the equation... [Pg.36]

Here FMF is the mean field free energy, defined for the lam hex and BCC phases in eqns 2.13-2.15. The term a = q 2/4ji 0 occurs in the expression for the mean square fluctuation... [Pg.81]

Figure 4.20 shows the correlation of experimental data of Hammerschmidt (1939) with five inhibitors with the pressure and temperature axes reversed from their normal position. The striking feature of Figure 4.20 is the parallel nature of all experimental lines, for the inhibition effect of both alcohols and salts relative to pure water. The parallel solid lines provide some indication of the molecular nature of the inhibition. Normally a phase transformation is considered relative to the change in Gibbs free energy defined as ... [Pg.230]

AGhydiuion hydration free energy defined as change in Gibbs energy from hypotheti-... [Pg.191]

The quantity (AH - TAS) is symbolized by AG. Thus, if a process occurs spontaneously, AG<0. The symbol G refers to the Gibbs free energy, defined as... [Pg.293]

Interfacial stractures in thermal equilibrium with a bulk electrode and a bulk electrolyte have the lowest interfacial free energy defined as ... [Pg.105]

Figure 7. A schematic representation of the solvent free energy functions involved in charge transfer reactions in the condensed phase. Indicated are the reaction free energy and the reorganization free energy defined in equations (22) and (27). The activation free energy and the photo absorption energy hco discussed below are also indicated. Figure 7. A schematic representation of the solvent free energy functions involved in charge transfer reactions in the condensed phase. Indicated are the reaction free energy and the reorganization free energy defined in equations (22) and (27). The activation free energy and the photo absorption energy hco discussed below are also indicated.
In Eq. 16.16, AG is the reaction free energy defined as the difference in the equilibrium free energies for the reactant and product surfaces ... [Pg.487]

Chen SW, Honig B. Monovalent and divalent salt effects on electrostatic free energies defined by the nonlinear Poisson-Boltzmann equation application to DNA binding reactions. J Phys Chem B 1997 101 9113-9118. [Pg.290]

Gx partial molar free energy defined below Eq. (14-16), energy units... [Pg.556]

Hi virtual value of the partial molar free energy defined by... [Pg.556]

Because the excess free energy defined by the expression... [Pg.318]

It is very attractive to couple the 3D-RISM method with the KS-DFT for the electronic structure to self-consistently obtain both classical and electronic properties of solutions and interfaces. The 3D-RISM approach using the 3D-FFT technique naturally combines with the KS-DFT in the planewave implementation. The planewave basis set is convenient for the simple representation of the kinetic and potential energy operators, and is frequently employed for large systems. The hybrid KS-DFT/3D-RISM method is illustrated below by the example of a metal slab immersed in aqueous solvent [28]. In a self-consistent field (SCF) loop the electronic structure of the metal solute in contact with molecular solvent is obtained from the KS-DFT equations modified for the presence of the solvent. The electron subsystem of the interface is assumed to be at the zeroth temperature, whereas its classical counterpart to have temperature T. The energy parameter of the KS-DFT is replaced by the Helmholtz free energy defined as... [Pg.240]

The free energy defined in Eqn (15.35) G(A) = —T In f Qxp[—V x,X)/T]dx. Along a single stochastic trajectory, the usual thermodynamic relations are valid for ensemble averages in equilibrium (Schmiedl and Seifert, 2007). Using the Fokker-Planck equation andD = Tp, with the Boltzmann constant assumed as unity, the rate of change of the trajectory-dependent total entropy of the system becomes... [Pg.672]

A sensitive test of the crossover behavior is obtained from an analysis of the effective critical exponent of the susceptibility (the third derivative of the free energy), defined as... [Pg.99]

More accurate results can be obtained by allowing for an arbitrary concentration profile c(r) inside the globule and minimizing the free energy (defined in eqns [87], ]74], [88]) with respect to c(r). Thus obtained transition point is ... [Pg.25]

The difference per temperature unit between the average energy and the free energy defines the configurational entropy, which can also be expressed in terms of the probabilities Pi"... [Pg.307]

Free Energy Defines Another Extremum Principle... [Pg.132]

Free Energy Defines Another Extrejvhjm Principle i s5... [Pg.135]


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See also in sourсe #XX -- [ Pg.6 , Pg.666 ]

See also in sourсe #XX -- [ Pg.6 , Pg.666 ]

See also in sourсe #XX -- [ Pg.668 ]

See also in sourсe #XX -- [ Pg.779 ]

See also in sourсe #XX -- [ Pg.794 , Pg.831 ]




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