Predictions magnetic properties

Dinuclear complexes with predictable magnetic properties. O. Kahn, Angew. Chem., Int. Ed. Engl., 1985,24, 834 (88). 

Both give the same picture, a triple bond composed of a cr bond and two tt bonds. Both predict the ion to be diamagnetic. Lewis structures deal well with diamagnetic (all electrons paired) species. The Lewis model cannot really predict magnetic properties. 57. O3 and N02 have identical Lewis structures, so we need to discuss only one of them. The Lewis structures for O3 are... 

EXAMPLE 24-4 Using the Spectrochemical Series to Predict Magnetic Properties... 

Small metal clusters are also of interest because of their importance in catalysis. Despite the fact that small clusters should consist of mostly surface atoms, measurement of the photon ionization threshold for Hg clusters suggest that a transition from van der Waals to metallic properties occurs in the range of 20-70 atoms per cluster [88] and near-bulk magnetic properties are expected for Ni, Pd, and Pt clusters of only 13 atoms [89] Theoretical calculations on Sin and other semiconductors predict that the stmcture reflects the bulk lattice for 1000 atoms but the bulk electronic wave functions are not obtained [90]. Bartell and co-workers [91] study beams of molecular clusters with electron dirfraction and molecular dynamics simulations and find new phases not observed in the bulk. Bulk models appear to be valid for their clusters of several thousand atoms (see Section IX-3). 

The toroidal and helical forms that we consider here are created as such examples these forms have quite interesting geometrical properties that may lead to interesting electrical and magnetic properties, as well as nonlinear optical properties. Although the method of the simulations through which we evaluate the reality of the structure we have imagined is omitted, the construction of toroidal forms and their properties, especially their thermodynamic stability, are discussed in detail. Recent experimental results on toroidal and helically coiled forms are compared with theoretical predictions. 

A major weakness of valence bond theory has been its inability to predict the magnetic properties of molecules. We mentioned this problem in Chapter 7 with regard to the 02 molecule, which is paramagnetic, even though it has an even number (12) of valence electrons. The octet rule, or valence bond theory, would predict that all the electrons in 02 should be paired, which would make it diamagnetic. 

Use the spectrochemical series to predict the effect of a ligand on the color, electron configuration, and magnetic properties of a d-metal complex (Examples 16.4 and 16.5). 

In their pursuit of determining solution structures of dinuclear copper complexes as carried out for complex (29) (Section 6.6.3.1.1). Comba reported complex (431) (r = 0.02 Cu-Cu 6.9 A, comparable with the values of 7.2 A predicted by molecular mechanics calculations and 6.7 A obtained from the simulated EPR spectrum).54 They reported369 complexes (432) (square planar) and (433) (Cu-Cu 3.35 A) as well. As part of studying magnetic properties of mono-, di-, and... 

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