By crystal field theory, write the electronic configuration of d⁶ regarding t_2g and, e_{. g.} in an octahedral field when Δ_o<P.

OR

Low spin configuration is rarely observed in tetrahedral coordination entity formation. Explain

t³_2g e³_g

Explanation:

Crystal field splitting in octahedral coordination entities:

In octahedral coordination entities, there are six ligands surrounding the metal atom/ion. The dorbitals get spilt into two sets- the t_2g set and the e_g set in crystal field splitting. The energy separation between the both is denoted

by _o. The t_2g orbitals are lower in energy, and e_gorbitals are higher in energy. The assigning of the electron to the orbitals is done on the basis of _o. and P(pairing energy).

Firstly. The electrons occupy t_2g orbitals single. For the fourth electron there can be two possibilities-

i. If _o < P ,the fourth electron enters one of the e_gorbitals to give

t³_2g e¹_g configuration. (This is the rule being followed in the above question)

ii. If _o > P ,the fourth electron enters one of the t_2g orbitals to give t⁴_2g e⁰_g configuration.

OR

The orbital splitting energies are not enough to force pairing.

Explanation:

In the formation of the tetrahedral complex, the energy involved in the splitting of D - orbital is very small compared to the energy involved in octahedral splitting. is very low. The orbital splitting energies are therefore not sufficient to force pairing. Hence low spin configurations are rarely observed in tetrahedral coordination entity formation