So if this is all by itself, we have no intermolecular bonds. If we place this pentane or some other alkane next to our neopentane, these two compounds will attract one another via intermolecular bonds. And in this case, in the case of alkanes, we have Vanderbilt forces. So the intermolecular bonds of alkanes are Vanderbilt forces. And these are simply instantaneous dipoles created between the protons found in the nuclei and the electrons surrounding or orbiting those nuclei. So these valuable forces exist only for a moment, and that's exactly why they are relatively weak forces compared to bonds like polar bonds.