Dear Student,
The intermolecular interaction are the interaction between two or more molecules which are adjacent to each other either it is attractive or repulsive.
The intermolecular interaction operates in between two nonpolar system is the instantaneous dipole induced interaction.
In this type of interaction suddenly due to any circumstances the instantaneous dipole created in any one of the molecule due to this other nonpolar molecule will get induced by it and dipole created on it and hence the intermolecular interaction comes into play.
Regards.