i know just this much about van der waals forces-
It is important to remember that van der Waals' forces are forces that exist between MOLECULES of the same substance Van der Waals forces act only over relatively short distances, and are proportional to the inverse of the seventh power of the intermolecular distances. The forces are important in the mechanics of ADHESION
is this much knowledge about it is ufficient for solving various questions based on it.
they use both attractive & repulsive forces to dictate how close molecules can be if they are nearby... they were one of the primary methods Watson and Crick used to deduce the structure of DNA! I'd say that's an important role.