Question

From the following option, NO+ ligand is:
A. Nitronium
B. Nitrosyl
C. Nitrosonium
D. Nitro

Answer 1

Hint: Ligands are those donor atoms or molecules which donate a pair of electrons to the central metal atom and form a coordinate bond with the central metal atom. Different types of ligands are named differently according to IUPAC.

Complete step by step answer: $N{O}^{+}$ is the type of positive ligand. According to the IUPAC nomenclature rule, the naming of positive ligands is done by adding “ium” at the end.
Since this is a nitroso compound and according to IUPAC nomenclature rule “ium” is added at the end. So its name will be nitrosonium ion.
So, the correct answer is “Option C”.
Additional Information: The nitrosonium ion is the one in which the nitrogen atom is bonded to the oxygen atom by a triple bond. Hence the bond order for nitronium ions is 3. It is obtained as the following salts $NOCl{O}_4,NOS{O}_{4}H$(Nitrosyl sulphuric acid) and $NOB{F}_4$. It also arises via the protonation of nitrous salt.
$HONO+H^{+}\to N{O}^{+}+H_{2}O$
This is a diatomic species having an overall positive charge and it readily reacts with water to form nitrous acid also. The molecular structure of the nitrosonium ion is given below:
$[N\equiv O{]}^{+}$
The bond length between N and O triple bonds is 106 pm.
Nitrosonium ion is an important intermediate in the formation of carcinogenic nitrosamine and DNA determination.

Note: Nitrosonium ion ($N{O}^{+}$) is isoelectronic with carbon monoxide, i.e. both nitrosonium ion and carbon monoxide have the same number of electrons. Also, its mode of coordination to metal atoms is similar to that of carbon monoxide. It is also isoelectronic with $C{N}^{-}$ and $N_2$.