Velence bond theroy describes the bonding in complexs in terms of coordinate -covalent bond resulting from overlap filled ligand orbitals with vacant metal hybrid orbitals This theory explains magnetic behaviour and geometrical shape of coordination compounds Magnetic moment of a complex compound can be determined experimentally and theoretically by using spin only formula
Magnetic moment `sqrtn (n+2)BM` (where n = No. unpaired electrons) .
The value of of spin only magnetic moment for octahedral complex of the following configuration is `2.84BM` The correct statement is
(a) `d^(4)` (in weak field ligand)
(b) `d^(2)` (in weak field and in strong field ligand)
(c) `d^(3)` (in weak field and in strong field ligand)
(d) `d^(5)` (in strong field ligand) .

Answer

B

Explanation

`Pgtdelta_(0)(n =4)`
`mu_(eff) = sqrt(n (n+2)) = sqrt(4(4+2))= sqrt(24) = 4.9 BM`
`PgtDelta_(0) (n =2)`
`mu_(eff) = sqrt8 = 2.89 BM`
(c ) `PltDelta_(0) (n =3)`
`mu_(eff) = sqrt15 = 3.8 Bm`
`Pgtdelta_(0) (n =1)`
`nu_(eff) = sqrt3 = 1.73 BM`