Also contains definition of: high-spin
In any @C01330@ with a particular dn (1<n<9) configuration and a particular geometry, if the n electrons are distributed so that they occupy the lowest possible energy levels, the entity is a low-spin complex. If some of the higher energy d orbitals are occupied before all the lower energy ones are completely filled, then the entity is a high-spin complex.
PAC, 1997, 69, 1251. (Glossary of terms used in bioinorganic chemistry (IUPAC Recommendations 1997)) on page 1283 [Terms] [Paper]