Question

The value of the 'spin only' magnetic moment for one of the following configurations is $2.84BM$. The correct one is:

• A. $d^4$ ( in strong ligand field)
• B. $d^4$ ( in weak ligand field)
• C. $d^3$ ( in weak as well as in strong ligand fields)
• D. $d^5$ ( in strong ligand field)

Answer 1

The correct option is A $d^4$ ( in strong ligand field)

Spin only magnetic moment = $\sqrt{n(n+2)}$ B.M.
Where, n = no. of unpaired electrons.
Given, $\sqrt{n(n+2)}$ = 2.84
or, n(n + 2) = 8.0656
or, n = 2
In an octahedral complex, for a $d^4$ configuration in a strong filed ligand, number of unpaired electrons = 2