The average static electric field experienced by an ion, molecule or atom in a crystal
generated by all the other surrounding atoms, molecules, or ions. The concept introduced
by
Becquerel and developed by Bethe has been extended to refer to the field generated by the
ligands (anions or neutral species) surrounding a transition metal ion in a
coordination compound. With the understatement that some covalency may exist in the metal-ligand
bond, it is often referred to as
ligand field.
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