Dipole-Dipole Forces

If you compare fluorine molecules F-F with H-Cl molecules, the molecules have the same shape and number of electrons.
Fluorine molecules are non-polar and hydrogen chloride molecules are polar.
All molecules have London forces, but H-Cl has additional permanent dipole-dipole interactions so has a higher boiling point.
In the solid state, simple molecules form a regular structure called a simple molecular lattice with molecules held in place by weak intermolecular forces.