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From spectroscopic parameters

In this case the donor acceptor coupling may be obtained by using (16.97)-(16.99) to estimate the couplings Fab and Fbd from spectroscopic parameters obtained from charge transfer donor-to-ligand and acceptor-to-ligand transitions. [Pg.589]

There is a nice point as to what we mean by the experimental energy. All the calculations so far have been based on non-relativistic quantum mechanics. A measure of the importance of relativistic effects for a given atom is afforded by its spin-orbit coupling parameter. This parameter can be easily determined from spectroscopic studies, and it is certainly not zero for first-row atoms. We should strictly compare the HF limit to an experimental energy that refers to a non-relativistic molecule. This is a moot point we can neither calculate molecular energies at the HF limit, nor can we easily make measurements that allow for these relativistic effects. [Pg.187]

From these parameters, a high charge density on the iron nucleus can be inferred. It is interesting to note that this situation is not reflected by the spectroscopic... [Pg.19]

It is interesting to note that the simple Morse potential model, when employed with appropriate values for the parameters a and D (a = 2.3 x 1010 m 1, D = 5.6 x 10 19 J as derived from spectroscopic and thermochemical data), gives fb = 6.4 nN and eb = 20%, which are quite comparable to the results obtained with the more sophisticated theoretical techniques [89]. The best experimental data determined on highly oriented UHMWPE fibers give values which are significantly lower than the theoretical estimates (fb 2 nN, b = 4%), the differences are generally explained by the presence of faults in the bulk sample [72, 90] or by the phonon concept of thermomechanical strength [15]. [Pg.108]

The parabolic model is, in essence, empirical because the parameter a is calculated from spectroscopic fa and v ) and atomic (/q and /q) data, while the parameter bre (or Ee0) is found from the experimental activation energies E(E= RT a(A/k)), where A is the pre-exponential factor typical of the chosen group of reactions, and k is the rate constant. The enthalpy of reaction is calculated by Equation (4.6). The calculations showed that = const, for structurally similar reactions. The values of a and bre for reactions of different types are given in Table 4.16. [Pg.188]

Spectroscopic Ellipsometry Porosimetry (EP). In general, ellip-sometry takes advantage of the change of polarization of a polarized light beam after reflection from a surface. From the parameters (T and A), obtained... [Pg.291]

At this point we have the geometrical and spectroscopic parameters necessary to calculate Ae(v) from the general DeVoe equations413. In the present case of two different oscillators we have... [Pg.133]

When using NMR as a detector for online separations, additional consideration must be given to how the sensitivity is affected by the movement of nuclei past the detector cell. Aside from the physical hardware setup, the chromatographic and spectroscopic parameters also play a role in the quality of the resulting data. Flow rate, solvent composition, and residence and acquisition times can be optimized to provide optimal results. NMR sensitivity and chromatographic resolution tend to have an inverse relationship with respect to online LC-NMR experiments. By slowing the flow rate, more scans can be acquired for a particular analyte in the flow cell, but... [Pg.360]

The C state has attracted much attention from spectroscopists because the state was believed to be the upper state of the ultraviolet absorption band which can help establish the accurate dissociation energy of the ground state of H2 [82]. Therefore, several attempts have been made to obtain the complete PEC for the C state [53,76,83,84]. The calculations by Browne revealed that there exists a suspicious maximum at i = 8a.u. which is about 160 cm above the dissociation limit [76]. This observation was consistent with the conclusion of Herzberg and Monfils that a maximum might exist in the vicinity of / — 13 a.u. [82]. The subsequent calculations by Kolos and Wolniewicz [53], and Namioka [77] refined the barrier to be about 105.5 cm at i = 9 a.u. The computed PEC for the C state and the fitted spectroscopic parameters (r, v, v Xe, a ) in the present study agree well with the experiment, as demonstrated by Table 8. [Pg.75]


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Spectroscopic parameters

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