what is p.pi-p.pi bonding??and also what is back bonding??
p π -p π bonding: When electron present in p orbital of an atom forms pi(π) bond with the electron present in p orbital of another atom then it is known as p π-p π bonding.
The following image shows p π-p π bonding between carbon atoms.
Back bonding: It is also called d π -p π bonding. When electron present in d orbital of an atom forms pi(π) bond with the electron present in p orbital of another atom then it is known as d π-p π bonding.
Given diagrams show back bonding: