Calculated splitting

This strong dependence of the conductivity on the composition can be understood qualitatively considering the densities-of-states. The DOS s from the LCAO calculation, splitted into their atomic contributions (partial DOS s), are given in Fig. 1 and can be discussed as follows ... 

A mean field theory for the stndy of solvent effects considers polarizable solvent molecules. The model, which combines qnantnm chemistry and simnlation calculations, splits the system into three parts ... 

We have already seen in Section 2 how barriers to inversion are obtained from the energy level splittings due to quantum mechanical tunneling. In this case the shape and the height of the potential curve are obtained by fitting the calculated splittings to the observed ones using Eq. (5) and (6). 

In the case of pyramidally planar A N-dimethyl vinylamine 133 of type 117, the HOMO lies at —8.01 eV and the calculated splitting between nl and n2 is 3.76 eV. Both values still do not match the experimentally observed range of values presented in Table 18, but calculated tertiary vinylamine values are shifted towards the experimental values of tertiary enamines. Especially, the calculated value for the second IP from n2 is calculated to be too high. For the rotated form of types 120 and 121 the calculated splitting is now 0.49 and 0.21 eV, less than in the case of 115 mentioned above. 

Table 3. Calculated splittings of HF/LF OH vibrations in CHA zeotype systems, compared experiment. ...

The experimental XANES spectrum has been reported by Li et al. [13] as shown in Fig 7, where the horizontal scale was calibrated by the data obtained by O Brien et al. [28]. As in the case of a-A Oa, the splitting of peak A is attributable to the spin orbit splitting. The calculated splitting of 2p orbital for a free Si atom using the Dirac-Fock-Slater method is 0.66 eV, which agrees well with the experimental splitting (0.6 eV). 

FIGURE 10. Calculated splittings and component decay constants of the luminescent excited state of ruthenocene (53). 

One of the results obtained for tetrahedral centers formed by 3d ions is that one for Mn " " (3d -configuration) in ZnS [47]. The splitting of the " Ti orbital triplet of Mn + ion was analyzed using the second-order effective spin-Hamiltonian and comparing the calculated splittings with the observed ones. The lowest estimate for the JT energy in ZnSMn " " was obtained to be 750 cm [47]. 

Figure 4-6. Evolution of the INDO/SCI-calculated splitting between the lowest two optical transitions of cofacial dimers formed by two PPV chains as a function of the inverse number of bonds (1/ n) along the conjugated backbone of the oligomer. The theoretical results are reported for interchain distances of 4 A (open circles) and 6 A (filled circles).

The calculated splitting of the 2H(2)11/2 levels in Er3+ [295] (and Nd3+ [296]) compounds is always smaller than experimental splitting. An empirical correction has been proposed which includes a multiplying factor for the fourth-order diagonal reduced CF matrix element (2H(2) C4 2H(2)). The correction is efficient for 2H(2)n/2 and 2H(2)9/2 and for those levels which are coupled to them by spin-orbit interaction, such as 4I9/2, 4F9/2 and 4Gn/2. With the multiplying factor 1.717, the mean deviation in fitting 58 levels of Cs2NaErCl6 was decreased by 18% [35]. This correction has approximately the same effect as the g40 A operator of the correlation CF. 

Table III shows that at SA separation, the excitations nicely classify as either excitonic or charge resonance (the combination of two charge transfer excitations that exactly cancel any net charge transfer in the state.). As shown in Table III, this is not the case for the system at 3.5 A. We note that at the sA separation there is a small splitting of 300 cm. of the two excitonic bands, and no calculated splitting of the two charge resonance bands calculated some 3,700 cm. higher in energy. From the Cl coefficients after projection the two lowest bands, Qyl and Qy2, are pure excitonic, the two higher, Qy3 and Qy4, pure charge resonance.

According to the results, the most intense band at 6.0 eV in the solution- and gas-phase spectra should be assigned as the 9 2— 2 i transition. The only possible alternative could be that it is in fact a superposition of both the transitions from 9t2 and 2e to 2t. However, the calculated splitting between both transitions is more than 0.6 eV, and one would therefore expect them to appear as distinct bands in the spectrum. We also notice that the highest charge transfer transition could just as well fall outside the range measured by the spectra, which never reached below 200 nm (above 6.2 eV). 

Finally, it was found that the spectra of Hj on Na,Ca-A revealed an ortho-para splitting of 4.5 cm of the main band (cf. Fig. 33), in excellent agreement with the calculated splitting (4.4 cm" ) reported in the same study. 

C,H,]- H HjC=C o)-CH2 ) Estimated values starting from calculated splittings l Hiickel and INDO calculations of coupling constar ") Determined on radical with 11 atom-% C in posi And reaction with (CH,),Si- or (CHjljSn- of corres ) SCF calculation of spin densities. in order to reproduce experimental spectr ts. tion 7. ponding benzyl chloride. um. 74Gey3... 

This value is in better agreement with calculated splitting than 0.500, which is possible too. 

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