Write the formula to calculate spin-only magnetic moment.

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

The spin-only magnetic moment is μ_so = √(n(n+2)) μ_B, where n is the number of unpaired electrons and μ_B is the Bohr magneton.

Many transition-metal complexes have magnetism dominated by electron spin, not orbital motion. In such cases we estimate the magnetic moment using only the count of unpaired electrons. This gives quick values that match experiments well for high-spin octahedral and tetrahedral complexes.

How to use

Find the metal’s oxidation state and d-electron count.
Decide high-spin or low-spin from ligand field strength (spectrochemical series).
Count unpaired electrons (n), then plug into √(n(n+2)).

Typical values

n (unpaired)	μ_so (μ_B)	Example complex
0	0	[Ni(CN)₄]²⁻ (square planar, low spin)
1	1.73	[Cu(H₂O)₆]²⁺
2	2.83	[V(H₂O)₆]²⁺
3	3.87	[Cr(H₂O)₆]³⁺
4	4.90	High-spin Fe²⁺ complexes
5	5.92	High-spin Mn²⁺ complexes