Ligand-field splitting

When Cr202 is introduced as an impurity into the a-Al202 lattice, as occurs in the semiprecious mineral mby, the color is red rather than the normal green. This color anomaly is the result of ligand field splitting of the Cr(III) ion (51,52). Chromium (ITT) also colors other minerals (53). 

Ligand field splittings in copper(II) compounds. D. W. Smith, Struct. Bonding (Berlin), 1972, 12, 49-112 (220). 

The complex Ti(H20)6]3+ absorbs light of wavelength 510. nm. What is the ligand field splitting in the complex in kilojoules per mole (kj-mol ) ... 

Ligand field splittings are normally reported as a molar energy, and so we need to multiply this expression by Avogadro s constant ... 

What is the value (in kilojoules per mole) of the ligand field splitting ... 

In octahedral complexes, the e -orbitals (dz< and dx2 -yi) lie higher in energy than the t2 -orbitals (dxy, dyz, and dzx). The opposite is true in a tetrahedral complex, for which the ligand field splitting is smaller. 

FIGURE 16.28 Tbe energy levels of the d-orbitals in a tetrahedral complex with the ligand field splitting A,. Each box (that is, orbital) can hold two electrons. The subscript g is not used to label the orbitals in a tetrahedral complex. 

Transitions between d-orbitals or between the ligands and the metal atom in complexes give rise to color the wavelength of d-d transitions can be correlated with the magnitude of the ligand field splitting. 

J 6 Determine the ligand field splitting from the wavelength of light absorbed by a complex (Example 16.3). 

The complex [Ni(NH3)6l2+ has a ligand field splitting of 209 kj-mol 1 and forms a purple solution. What is the wavelength and color of the absorbed light ... 

Libby, W., 713 ligand, 671, 672 ligand field splitting, 682 ligand-field theory, 688 ligand-to-metal transition, 686 light, 4, 6... 

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