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Questions
State the superiority of crystal field theory over valence bond theory.
Why is crystal field theory regarded superior to valence bond theory?
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Solution
Despite the constraints mentioned above, crystal field theory outperforms valence bond theory. The crystal field theory is thought to be preferable to the valence bond theory for the following reasons.
- Crystal field theory describes the magnetic properties of complexes in detail and provides an explanation for how magnetic moments vary with temperature. VBT fails to provide these additional details.
- Crystal field theory measures the stability of a complex. With this measure, the geometry gained by a particular complex can be predicted. VBT does not include such a measure.
- Crystal field theory explains certain thermodynamic and kinetic features of complexes. VBT does not offer such an explanation.
- Only crystal field theory can explain the observed d-d transitions in complexes and their hue. The VBT does not explain spectroscopic features or complex coloration adequately.
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OR
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