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Question
What can be inferred from the magnetic moment value of the following complex species?
| Example | Magnetic Moment (BM) |
| K2[MnCl4] | 5.9 |
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Solution
Magnetic Moment (μ) = `sqrt(n(n + 2))` BM
When n = 1,
μ = `sqrt(1(1 + 2))`
= `sqrt 3`
= 1.73 BM
≈ 2
When n = 2,
μ = `sqrt(2(2 + 2)`
= `sqrt 8`
= 2.83 BM
≈ 3
When n = 3,
μ = `sqrt(3(3 + 2))`
= `sqrt 15`
= 3.87 BM ≈ 4
When n = 4,
μ = `sqrt(4(4 + 2))`
= `sqrt 24`
= 4.90 BM
≈ 5
When n = 5,
μ = `sqrt(5(5 + 2))`
= `sqrt 35`
= 5.92 BM
≈ 6
K2[MnCl4]: μ = 5.9 BM, Mn2+ ion has 5 unpaired electrons. Its orbital diagram is:
| 3d | ||||
| ↑ | ↑ | ↑ | ↑ | ↑ |
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