Question

Which one of the following is a tetrahedral complex as well as diamagnetic in nature?

Options

• [Ni(CN)₄]²⁻

• [NiCl₄]²⁻

• [Cu(NH₃)₄]²⁻

• [Ni(CO)₄]

Answer 1

[Ni(CO)₄]

Explanation:

In Ni(CO)₄, nickel is in the 0 oxidation state. Strong-field CO ligands cause the metal to adopt a d¹⁰ configuration, and the metal uses one 4s and three 4p orbitals to form sp³ hybrids, giving a tetrahedral geometry with all electrons paired, which is diamagnetic.