Question

Which of the following will form an octahedral complex?

• A. $d^4$ (low spin)
• B. $d^8$ (high spin)
• C. $d^5$ (low spin)
• D. All of these

Answer 1

Answer: (C)

$d^5$ (low spin)

An octahedral complex will be formed by $d^5$ low spin. Out of 5 d orbitals, 3 will contains electrons and 2 will be empty. These 2 empty d orbitals can undergo $s{p}^3{d}^2$ hybridisation (or $d^{2}s{p}^3$ hybridisation) to form octahedral complex.