Bonding in Metal Carbonyls

Write a short note on bonding in metal carbonyls.

The correct pair of orbitals involved in $\pi$ -bonding between metal and $\mathrm{CO}$ in metal carbonyl complexes is:

Carbon monoxide is a very common ligand in organometallic chemistry. It is particularly good at stabilising low oxidation states of central metal such as Fe(CO)₅.

When $\mathrm{CO}$ approaches metal as ligand, a sigma bond is formed as a result of overlap of lone pair of carbon atom and empty hybridised orbital of metal. Apart from it, empty $\mathrm{CO}$ antibonding orbital accepts $\text{π}$-electron density from the filled $\mathrm{d}$-orbitals on the metal atom side by side, which is sometimes also referred as $\text{π}$-back bonding.

Carbon monoxide is not appreciably nucleophilic, i.e., $\text{σ}$-bond formed with metal is weak. But many $\mathrm{d}$-metal carbonyl compounds are very stable. Thus, we can infer that the strength of $\text{π}$-back bonding enhances the stability of carbonyl complexes by increasing the strength of $\text{σ}$-bond between metal and carbonyl.

Which of the following has shortest metal carbon bond ?

Carbon monoxide is a very common ligand in organometallic chemistry. It is particularly good at stabilising low oxidation states of central metal such as Fe(CO)₅.

When CO approaches metal as ligand, a sigma bond is formed as a result of overlap of lone pair of carbon atom and empty hybridised orbital of metal. Apart from it, empty CO antibonding orbital accepts $\text{π}$-electron density from the filled d-orbitals on the metal atom side by side, which is sometimes also referred as $\text{π}$-back bonding.

Carbon monoxide is not appreciably nucleophilic, i.e., $\text{σ}$-bond formed with metal is weak. But many d-metal carbonyl compounds are very stable. Thus, we can infer that the strength of $\text{π}$-back bonding enhances the stability of carbonyl complexes by increasing the strength of $\text{σ}$-bond between metal and carbonyl.

The longest $\mathrm{CO}$ bond length will be with

Correct statement for these compounds is :

(i) $\mathrm{Co}{\left(\mathrm{CO}\right)}_6$

(ii) $\mathrm{Co}{\left(\mathrm{CO}\right)}_5{\mathrm{NH}}_3$

(iii) $\mathrm{Co}{\left(\mathrm{CO}\right)}_4{\left({\mathrm{NH}}_3\right)}_2$

(iv) $\mathrm{Co}{\left(\mathrm{CO}\right)}_3{\left({\mathrm{NH}}_3\right)}_3$

(v) $\mathrm{Co}{\left(\mathrm{CO}\right)}_2{\left({\mathrm{NH}}_3\right)}_4$

(vi) $\mathrm{Co}\left(\mathrm{CO}\right){\left({\mathrm{NH}}_3\right)}_5$

Among the following metal carbonyls, the $C-O$ bond order is lowest in

The correct order of $\mathrm{M}-\mathrm{C}\mathrm{\pi }$ bond and strength in given metal carbonyls is -

The correct order of $\mathrm{M}–\mathrm{C}\mathrm{ }\mathrm{\pi }$ bond and strength in given metal carbonyls is -

Which of the following organometallic compound is $\sigma$and $\pi$ bonded?

Metal Carbonyls In $\mathrm{F}\mathrm{e}{\left(\mathrm{C}\mathrm{O}\right)}_5$, the $\mathrm{F}\mathrm{e}-\mathrm{C}$ bond has:

Among the following metal carbonyls, $\mathrm{C}—\mathrm{O}$ bond order is lowest in which of the following?

The most unstable carbonyl complex among the following is

Which of the following metal carbonyls has the highest value of $\mathrm{M}–\mathrm{C}$ bond order?

Choose the correct of M – C bond order in the following molecule and ions

Which of the following statement(s) is/are true?

In the isoelectronic series of metal carbonyl, the $\mathrm{CO}$ bond strength is expected to increase in the order:

Which of the following carbonyls will have the strongest C - O bond ?

Among the following metal carbonyls, the $\mathrm{C}—\mathrm{O}$ bond order is lowest in