ligand field

https://doi.org/10.1351/goldbook.LT06764
Ligand field theory is a modified @[email protected] theory that assigns certain parameters as variables rather than taking them as equal to the values found for free ions, thereby taking into account the potential covalent character of the metal-ligand bond.
Source:
PAC, 1997, 69, 1251. (Glossary of terms used in bioinorganic chemistry (IUPAC Recommendations 1997)) on page 1283 [Terms] [Paper]