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Planck function defined

Planck function - A thermodynamic function defined by T = -GIT, where G is Gibbs energy and T thermodynamic temperature. [2]... [Pg.113]

This expression is valid for the transition from the state i with energy Ej to the state / with energy Ef, where hcbif = Ef — Ei, Na is the Avogadro constant, h is Planck s constant, c is the speed of light in vacuum, k is the Boltzmann constant, Cq is the permittivity of free space, and, finally, Q is the partition function defined as g = 6xp(—Uy/kr), where gj is the total... [Pg.184]

In this equation, H, the Hamiltonian operator, is defined by H = — (h2/8mir2)V2 + V, where h is Planck s constant (6.6 10 34 Joules), m is the particle s mass, V2 is the sum of the partial second derivative with x,y, and z, and V is the potential energy of the system. As such, the Hamiltonian operator is the sum of the kinetic energy operator and the potential energy operator. (Recall that an operator is a mathematical expression which manipulates the function that follows it in a certain way. For example, the operator d/dx placed before a function differentiates that function with respect to x.) E represents the total energy of the system and is a number, not an operator. It contains all the information within the limits of the Heisenberg uncertainty principle, which states that the exact position and velocity of a microscopic particle cannot be determined simultaneously. Therefore, the information provided by Tint) is in terms of probability I/2 () is the probability of finding the particle between x and x + dx, at time t. [Pg.3]

Before embarking on this discussion one fact must be established. In many applications the autocorrelation function of L(t) is not really a delta function, but merely sharply peaked with a small rc > 0. Accordingly L(t) is a proper stochastic function, not a singular one. Then (4.5) is a well-defined stochastic differential equation (in the sense of chapter XVI) with a well-defined solution. If one now takes the limit rc —> 0 in this solution, it becomes a solution of the Stratonovich form (4.8) of the Fokker-Planck equation. This theorem has been proved officially, but the result can also be seen as follows. [Pg.232]

Since a molecule has translational, rotational, vibrational and electronic energy levels it is possible to define q for all four cases. Vibrational energy e is given hy e = hv, where h is Planck s constant, and V the frequency of vibration. The vibrational partition function q is then obtained by taking the sum over all tihe vibrational energy levels defined by the vibrational quantum number v. This is... [Pg.85]

Radiation emitted by the lamp is caused by the temperature achieved by its filament, which in turn depends on the power input on the lamp. The radiation spectral distribution is a function of the temperature of the source and the wavelength, and this relationship is defined by the Planck black body equation ... [Pg.3393]

Planck-Einstein function which occurs in c (T), it is possible to define a temperature T such that for most practical purposes... [Pg.121]


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See also in sourсe #XX -- [ Pg.163 ]




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