Question

What can be inferred from the magnetic moment value of the following complex species?

Example	Magnetic Moment (BM)
[Fe(H2O)6]2+	5.3

Answer 1

Magnetic Moment (μ) = `sqrt(n(n + 2))` BM

When n = 1, μ = `sqrt(1(1 + 2))` = 1.73 BM ≈ 2

When n = 2, μ = `sqrt(2(2 + 2)` = 2.83 BM ≈ 3

When n = 3, μ = `sqrt(3(3 + 2))` = 3.87 BM ≈ 4

When n = 4, μ = `sqrt(4(4 + 2))` = 4.90 BM ≈ 5

When n = 5, μ = `sqrt(5(5 + 2))` = 5.92 BM ≈ 6

[Fe(H₂O)₆]²⁺: μ = 5.3 BM corresponds to 4 unpaired electrons. The configuration of Fe²⁺ ion is [Ar]3d⁶, and the orbital diagram is:

3d
↑↓	↑	↑	↑	↑