According to the valence bond theory, the metal atom or ion under the influence of ligands can use its (n-1)d, ns, np, nd orbitals for hybridization to yield a set of equivalent orbitals of definite geometry. These hybridized orbitals are allowed to overlap with ligand orbitals that can donate electron pairs for bonding. It is usually possible to predict the geometry of a complex from the knowledge of its magnetic behaviour on the basis of the valence bond theory. Consider the formation of \([Co(NH_3)_5Cl]Cl_2\) and answer the following question:

The spin only magnetic moment of the complex \([Co(NH_3)_5Cl]Cl_2\)  in BM is:

0.0

Due to the presence of a strong field ligand, \(NH_3\) electrons of d-orbitals pair up so there is zero unpaired electrons to show spin only magnetic moment is :

\(\sqrt{0(0+2)} = 0\) BM