Which of the following is true?
1) M-C bond in metal carbonyls possesses both sigma π character
2) The M-C o bond is formed by the donation of pair of electrons on carbonyl into a vacant orbital of the
metal
3) The M-C a bond is formed between filled d orbitals of metal and vacant i orbital of CO
4) Both A&B
Answers
Filled π orbital of Carbon Monoxide overlaps with empty d orbital of metal to form Sigma bond
in this one electron pair (lone pair) of Carbon atom is donated into vacant orbital of metal.
Filled d-orbital of metal overlaps with empty antibonding π orbital of CO resulting in formation of π orbital.
So, bond shows both Sigma and pi character also lone pair is donated in empty orbital of metal.
Answer:
It is a covalent bond formed by a coaxial overlap of bonding orbitals. It is a very strong bond, due to a greater extent of overlapping. It is possible between any two orbitals s-s, p-p or s-p and also hybrid orbitals. Bond energy is more.
Characteristics of pi bonds :
Pi bonds are weaker bond.
Pi bonds are bonds with less energy.
Electronic cloud is present upper or lower to bonded nuclei.
Only un hybridized orbitals form pi bond.
Pi bond can not exist independently.
Double bond contain one pi bond and triple bond contain two pi bond.
Option (4) Both A and B
Filled π orbital of Carbon Monoxide overlaps with empty d orbital of metal to form Sigma bond
in this one electron pair (lone pair) of Carbon atom is donated into vacant orbital of metal.
Filled d-orbital of metal overlaps with empty antibonding π orbital of CO resulting in formation of π orbital.
So, bond shows both Sigma and pi character also lone pair is donated in empty orbital of metal.