Question

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

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

Answer 1

Answer: (D)

(a) $d^5$ in strong field
n = unpaired electron = 1
Magnetic moment $= \sqrt{n\left(n + 2\right)}BM$
$= \sqrt{3} BM = 1.73 \,BM$
$\left(b\right) d^{3}$ in strong/weak field
$n = 3$
Magnetic moment $= \sqrt{15} = 3.87\,BM$
$\left(c\right) d^{4}$ in weak field
$n = 4$
Magnetic moment $=\sqrt{24} = 4.90\,BM$
$\left(d\right) d^{4 }$ in strong field
$n = 2$
Magnetic moment $=\sqrt{8} = 2.83 \,BM$