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Exponential part

Note that only the polynomial factors have been given, since the exponential parts are identical for all wave functions. Of course, any linear combination of the wave functions in Eqs. (D.5)-(D.7) will still be an eigenfunction of the vibrational Hamiltonian, and hence a possible state. There are three such linearly independent combinations which assume special importance, namely,... [Pg.621]

Activation energy E, The eonstant in the exponential part of the Arrhenius equation, assoeiated with the minimum energy differenee between the reaetants and an aetivated eomplex (transition state that has a stmeture intermediate to those of the reaetants and the produets), or with the minimum eollision energy between moleeules that is required to enable a reaetion to oeeur. [Pg.1010]

Assuming that the function form of lG with regard to the applied overpotential V is determined by the exponential part, under the condition of constant NaCl concentration, lG is also expressed as a function of the applied overpotential V as follows,... [Pg.294]

Equation (1.12) describes an ORR rate dependence on potential that derives from two dijferent redox potentials, one affecting the exponential part of the expression and the other affecting the pre-exponential part. The term depending on — q2/h o reflects the lowering of the activation energy at an active metal site by an increase in cathode overpotential, whereas the term depending on ( pt(H20)/Pt-OHads describes the fraction of active metal sites, (1/Z + 1), at some value of . Equation (1.12) suggests... [Pg.25]

From a physical point of view, this new formulation includes exponential terms that are in agreement with the observed ab initio and experimental results. Moreover, it is easy to verify that the new expression converges to the classical one when r increases. That way, at long range, where the multipolar approximation is valid, the exponential part dies whereas, at short distances, the monopole-monopole interaction embodies a part of the penetration energy. Consequently, Emono-mono has the correct dependence at any range. [Pg.153]

The coefficient is merely a decimal number written in the ordinary way. That coefficient is multiplied by the exponential part made up of the base (10) and the exponent. (Ten is the only base which will be used with numbers in exponential form in the general chemistry course.) The exponent tells how many times the base is multiplied by the coefficient ... [Pg.14]

When two numbers in exponential form are multiplied, the coefficients are multiplied and the exponential parts are multiplied separately. The answer is the product of these two answers ... [Pg.15]

It is apparent that the number of 10s in the answer—the exponent of the answer—is merely the sum of the exponents of the factors. Hence, the rule for multiplying exponential parts of exponential numbers (having the same base) is to add exponents. This rule saves us from having to write out the 10s each time we multiply. [Pg.15]

To divide exponential numbers, divide the coefficients and divide the exponential parts separately. To divide the exponential parts merely subtract exponents. [Pg.15]

You can move the exponential part of a number from numerator to denominator or vice versa merely by changing the sign of the exponent. [Pg.15]

When we add or subtract, we always align the decimal points beforehand. In the case of exponential numbers, that means that we add or subtract only numbers having the same exponential parts. The exponent of the answer is the same as the exponent of each of the values added or subtracted. [Pg.16]

Since the exponents are not the same, we cannot merely add the coefficients. What we must do is change the coefficient and exponential part of one of the numbers so that the value remains the same but the exponent matches the exponent of the other number ... [Pg.16]

The exponential part of the product is divided by 10 therefore the coefficient is multiplied by 10. Thus, the product is multiplied by 10/10 = 1, and the value of the product is unchanged. Alternatively, for each place that you move the decimal to the right, subtract 1 from the exponent. For each place that you move the decimal left, add 1 to the exponent. Check yourself to sec that you have increased the coefficient and decreased the exponent... [Pg.16]

To raise an exponential number to a power, raise both the coefficient to the power and the exponential part to the power. To do the latter, multiply the original exponent by the power ... [Pg.16]

Ans. No zeros are needed for the sole purpose of determining the magnitude of the number. (The exponential part of the number does that.) The only other reason a 0 would be present is that it is significant. [Pg.36]

Activation energy the constant Ea in the exponential part of the Arrhenius equation associated with the minimum energy difference between the reactants and an activated complex (transition state), which has a structure intermediate to those of the reactants and the products, or with the minimum collision energy between molecules that is required to enable areaction to take place it is a constant that defines the effect of temperature on reaction rate. [Pg.227]

An outstanding feature of the Weibull distribution is that it provides a clear separation of this parameter from the exponential part reflecting rate and shape of the profile. [Pg.256]

The temporal evolution of the simulated peak position of the fluorescence spectrum is shown in Fig. 3a The corresponding experimental peak-shift (figure 2 in [5]) consists of an oscillatory and an exponential part. Our model reproduces the weakly damped oscillatory part of the peak shift, but does not describe the large Stokes shift of 1400 cm-1. The reason is that our single-mode model does not take into account other system modes and, what is more important, solvent modes, which contribute to the overall shift of the SE spectrum. The model may be improved by including an additional overdamped solvent mode. [Pg.305]

As discovered in ref. 63, the addition of tetranitromethane, C(N02)4, electron acceptor to a solution of CuP in ethanol causes a decrease in the quantum yield of phosphorescence of CuP at 77 K and the appearance in the optical and the EPR spectra of signals which are characteristic of CuP+, NOo, and C(N02)3" particles. The formation of these particles points to electron phototransfer from CuP to C(N02)4. The decay curves of CuP phosphorescence in vitreous solutions containing C(N02)4 in low concentrations are of an exponential character. At sufficiently high concentrations of C(N02)4 (0.3-0.5M), however, these curves deviate from the simple exponential form. The appearance of non-exponential parts on the decay curves has been accounted for by electron tunneling from the triplet excited state of CuP particles to molecules of C(N02)4. [Pg.300]

In order to investigate the quantum number dependence of vibrational dephasing, an analysis was done on two systems C-I stretching mode in neat-CH3I and C-H mode in neat-CHCl3 systems. The C-I and C-H frequencies are widely different (525 cm-1 and 3020 cm-1, respectively) and so also their anharmonic constants. Yet, they both lead to a subquadratic quantum number dependence. The time-dependent friction on the normal coordinate is found to have the universal nonexponential characteristics in both systems—a distinct inertial Gaussian part followed by a slower almost-exponential part. [Pg.169]

In the normal range of temperatures used in NMR experiments, the major source of variation of rjj1 with temperature is contained in the exponential part. In other words, a plot of logxm against /T (Arrhenius plot) will give a fairly straight line. Given the linear relationship between and the relaxation rates,... [Pg.128]

If there are no multiple crossings of the line and the exponential part,... [Pg.78]

Compared to solveadiabxy. m for the adiabatic CSTR case in Section 3.1, the above MATLAB function solveNadiabxy. m depends on the two extra parameters Kc and yc that were defined following equation (3.9). It uses MATLAB s built-in root finder fzero.m. As explained in Section 3.1, such root-finding algorithms are not very reliable for finding multiple steady states near the borders of the multiplicity region. The reason - as pointed out earlier in Section 1.2 - is geometric the points of intersection of the linear and exponential parts of equations such as (3.16) are very shallow, and their values are very hard to pin down via either a Newton or a bisection method, especially near the bifurcation points. [Pg.95]

Similarly, NadiabNisoplotfgxA.m plots the linear and exponential parts separately, first of the two equations (3.16) in terms of xa, and then of (3.11) in terms of y in more detail, while NadiabNisoplotfgxAy, m creates the following three graphs first it repeats the linear and exponential parts plot of (3.16), followed by plotting the equation (3.16) converted to standard form, i.e., converted to an / equal to zero equation. And finally the same is done with equation (3.14). These differing plots are useful when one is trying... [Pg.96]

The experimental decays iB(t) of the 350 nm band have been compared with curves calculated (solid lines in Fig. 5.1) by adjusting the parameters t" and r° in Eqs. (4.218) and (4.219) the spontaneous decay rate kr has been approximated by the value kB = kf + kB measured in a nonpolar solvent. It should be noted that with the photon-counting detection method the investigation of the fast initial nonexponential decay is hindered at low viscosity by poor resolution and only the exponential part of the decay is observable. At high viscosities (i7>100cp) the deviation from an exponential law is clearly visible. For the streak camera measurements the observations are opposite to those previously mentioned at high viscosities the semilogarithmic plot of iB(f) appears linear, whereas at low viscosities the decay shows nonexponential behavior. In Fig. 5.2 are represented the actual B decays calculated with the best fit values of the two relaxation times t° and r". Their variation with the temperature has also been examined Fig. 5.3 shows that they follow well those of -q/T and 17, respectively, as expected from the expressions (4.216) and (4.220) ... [Pg.142]


See other pages where Exponential part is mentioned: [Pg.269]    [Pg.14]    [Pg.29]    [Pg.29]    [Pg.40]    [Pg.148]    [Pg.107]    [Pg.64]    [Pg.18]    [Pg.103]    [Pg.360]    [Pg.123]    [Pg.41]    [Pg.295]    [Pg.296]    [Pg.301]    [Pg.14]    [Pg.77]    [Pg.78]    [Pg.78]    [Pg.37]    [Pg.135]    [Pg.139]    [Pg.574]   
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See also in sourсe #XX -- [ Pg.33 ]

See also in sourсe #XX -- [ Pg.16 ]

See also in sourсe #XX -- [ Pg.2 , Pg.12 ]




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Exponential part Exponentiation

Exponential part Exponentiation

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