Tetrahedral Splitting
The division of d orbitals under a tetrahedral field, with the e set below the t₂ set and a much smaller gap.
Formula / equation
Δ_t = (4/9)Δ₀
Unit
cm⁻¹
In depth
The ordering is inverted relative to the octahedral case because no ligand points directly at any d orbital. With only four ligands and poorer alignment, the splitting is less than half the octahedral value, which is why tetrahedral complexes are essentially always high spin.
Examples in the real world
[CoCl₄]²⁻ being intensely blue and high spin, in contrast to the pale pink octahedral aqua complex.