SCF-Xa-SW Calculations

Thus, the SCF-Xa-SW calculations for the metal dimers confirm the anomaly of the technetium clusters that was experimentally observed in previous studies [9-11], It should be noted that because the actual structure of the... 

SCF-Xa-SW calculations were executed in double precision on a Honeywell 6000 computer using current versions of the programs written originally by K. H. Johnson and F. C. Smith. 

The Os(III) dimers, [Os2X8]2- (X = Cl", Br, or I") each have an Os=Os triple bond and terminal halogens. They have been characterized by X-ray diffraction, IR and UV/Vis spectroscopies, and electrochemistry (232, 520-523). The complexes have also been subjected to SCF-Xa-SW calculations of the energies of their electronic states (521). 

Fig. 11. Molecular orbital diagram for the MojClJ" ion based on SCF-Xa-SW calculations the highest tilled level is 22>2g(fi) (199).

These results have led us to a more quantitative evalutation of the bonding in the blue copper site through a many electron SCF-Xa-SW calculation (14). The structures calculated include the free ligands and approximations to the site shown in Figure 5 with the Xa-SW parameters as indicated. 

Figure 5. Top Approximations considered by SCF-Xa -SW calculation. Bottom X ct parameters for CuCSCCH ) )(SCH )(NH. ...

An important comparative study has been made of the Mo-Mo and W-W quadruple bonds in M2Cl4(PMe3)4 using SCF-Xa-SW calculations and PE spectroscopy93. Section 5.5 should be consulted for further details. 

Fig. 6. Contour plot of the aIg MO wavefunction resulting from SCF-Xa-SW calculations. The amplitude of the wavefunction changes from one plot to the other by a factor of three. Inter-molecular distances Pt-C = 2.02 A, C-N = 1.11 A60 ...

Sy overlap integrals I, Ij ionization potentials, values from the SCF-Xa-SW calculations of Ref. 60) the structures of the valence and the conduction bands are obtained for different R values as shown in the upper part of Fig. 9. 

The dinuclear complexes [MX(PF3)2]2 (M = Rh, Ir X = Cl, Br, I) are sufficiently volatile for their He(I) and He(II) photoelectron spectra to be recorded (288, 289) and the data have assisted in the assignments of bands in the photoelectron spectra of the corresponding carbonyl complexes for which transition state SCF-Xa-SW calculations of ionization energies have been made. 

Given the above bonding scheme, the small A value in the EPR spectrum arises not, as often suggested, from the distorted geometry of the site, but rather from delocalization of the unpaired electron onto the ligands. SCF-Xa-SW calculations suggest the half-occupied orbital has only ca. 42% copper character and about 36% sulfur pir. 

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