Which theory discusses the relationship between ligand bonding and degradation of d orbitals in metal complexes and the geometry of metal complexes and the splitting of d orbitals?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. Crystal field theory (CFT)
| Crystal field theory (CFT) | It illustrates how the presence of ligands in transition metal complexes causes the breaking of orbital degeneracy. The strength of the metal-ligand bonds is qualitatively described by CFT. The energy of the system changes depending on how strong the metal-ligand connections are. This could result in both a change in color and magnetic characteristics. John Hasbrouck van Vleck and Hans Bethe created this notion. |
| CFT octahedral complexes |
A positively charged metal ion interacts electrostatically with six negatively charged ligands or with the negative ends of dipoles connected to the six ligands to produce an octahedral metal complex, according to CFT. The ligands also interact electrostatically with one another. |
Splitting of the Crystal Field in the Octahedral Complex
- We detect repulsion between d orbital electrons and ligand electrons in the instance of an octahedral coordination combination with six ligands encircling the metal atom/ion.
- As they point in the direction of the axes along the ligand, the dx2-y2 and dz2 orbitals are more susceptible to this repulsion.
- They, therefore, have more energy than is typical in the spherical crystal field.
- The repulsions experienced by dxy, dyz, and dxz orbitals are lower since they are oriented between the axes.
- As a result, the energy of these three orbitals is lower than the mean energy of the spherical crystal field.
Two energy levels result from the repulsions in the octahedral coordination compound:
- t2g– set of three orbitals (dxy, dyz, and dxz) with lower energy
- eg – set of two orbitals (dx2-y2 and dz2) with higher energy