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Energy, defined

This equation results from the assumption that the actual reaction step in themial reaction systems can happen only in molecules (or collision pairs) with an energy exceeding some tlireshold energy Eq which is close, in general, to the Arrhenius activation energy defined by equation (A3.13.3). Radiative energization is at the basis of classical photochemistry (see e.g. [4, 3 and 7] and chapter B2.5) and historically has had an interesting sideline in the radiation... [Pg.1045]

An estimate of AR ia alloys can be made usiug the empirical expression (12) of equation 10 where the average alloy reduced energy, is defined by equation 11, where C (i = 1, 2,... , n) is the elemental atomic fraction of the /th element, and is the elemental reduced energy defined iu equation 3. Using this formulation, the projected range straggling iu compounds can be calculated to within 20%. [Pg.394]

On the other hand, the bond density surface is able to provide quantitative information The three surfaces shown below correspond, respectively, to the reactant, the transitioi state (a transition state is a molecule that is on the way to becoming the products an< its energy defines how fast the reaction can proceed), and the two products. [Pg.26]

For the phase stability analysis we follow the method given by Kanamori and Kakehashi of geometrical inequalities and compute the antiphase boundary energy defined by... [Pg.28]

The subscript i labels the six concentrations and energies defined previously. It is straightforward to show that by minimising G with respect to the c, subject to the three constraints, we recover the three equations for the q predicted by the law of mass action. [Pg.344]

Other thermodynamic functions described above in that the change in free energy AG is determined solely by the initial and final states of the system. The maximum work, or maximum available energy, defined in terms of the Gibbs free energy G, which is now called the free enthalpy, is... [Pg.1225]

It has been pointed out by Bartlett (1955) that a much more sensitive criterion for the local accuracy of an approximate wave function 0 is provided by the local energy defined by the relation... [Pg.299]

In the case of the s wave (/ = 0) of the optimised orbital the effective energy defined in the section 2 is given here by Ce// = e- -l/R = -0.602H (R is the internuclear distance). According to the analysis of that section it is seen on the fig.(9) that the s wave of the optimum orbital obtained in the gaussian basis is actually very close to the numerical regular atomic s orbital with 6 // = -0.602 H while the s wave of the un-optimised orbital is significantly different from these two functions. [Pg.32]

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 same problem can be treated from a slightly different perspective. Motivated by the fact that it is the inverse temperature that is thermodynamically conjugate to the energy, define the zeroth temperature [1, 3] as... [Pg.59]

The key to understanding reaction equilibrium is the Gibbs free energy, ox free energy, defined as1-4 ... [Pg.97]

Formation of the mono- and dinitrosyl complexes is a thermodynamically favorable process, which distinctly depends on the electronic configuration of the metal center. The adsorption energy, defined as A=. Eaddukt - ( mzsm-5+ no)> is shown in the form of a histogram in Figure 2.16. Formation of mononitrosyl complexes is exothermic... [Pg.49]

To obtain explicit expressions for the energies, define two matrices A and... [Pg.94]

The fitting of electronegativities and hardnesses is done independently of each other with the help of a reformulation of the fluctuating charge model in terms of a linear response model [117, 120, 210], In the presence of an external potential the electrostatic energy defined in Eq. (9-35) is ... [Pg.244]

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]

To put the previous statement into perspective it is necessary to stipulate that any macrosystem with well-defined values of its extensive parameters is made up of myriads of individual particles, each of which may be endowed with an unspecified internal energy, within a wide range consistent with all external constraints. The instantaneous distribution of energy among the constituent particles, adding up to the observed macroscopic energy, defines a microstate. It is clear that any given macrostate could arise as the result of untold different microstates. [Pg.428]

Electron Volt (eV) A non-SI unit of energy defined as the energy acquired by a particle containing one unit of charge through a potential difference of one volt,... [Pg.5]

Having established rhythmic breathing and the Middle Pillar as before, circulate the light from Kether to Malkuth, down and up the sides of your sphere of sensation, for at least six full cycles. Next, circulate the energy from Kether to Malkuth, down the front and up the back of your sphere of sensation, for at least six full cycles. These circulations of energy define the perimeters of the alchemical vessel, the aura. [Pg.26]

Several attempts on theoretical prediction of yt are found in the literature according to some models, yx is more closely related to the cuticular energy defined in Chapter V than to the true surface energy, but cuticular energy implies no contractile tendency and cannot pull along the line KO of Fig. 12. [Pg.41]

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]


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Defining Energy

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