Question

Explain why in tetrahedral coordination entities, low-spin configurations are rarely observed.

Hint:

Low-spin configurations are more common in octahedral complexes with strong field ligands, not tetrahedral ones.

Answer 1

In tetrahedral geometry, the crystal field splitting energy ($\Delta_t$) is smaller than in octahedral geometry. The smaller splitting does not favor pairing of electrons, and hence, high-spin configurations are more likely to occur. Therefore, low-spin configurations are rarely observed in tetrahedral complexes.