In iodine I2 molecules, the primary type of intermolecular force present is London dispersion forces, also known as van der Waals forces. These forces are weak and temporary, arising from the fluctuations in electron distribution around the iodine atoms, which create temporary dipoles that attract other iodine molecules.The London dispersion forces in I2 contribute to its physical properties, such as melting and boiling points. Since these forces are relatively weak, the energy required to overcome them is not very high. As a result, iodine has a relatively low melting point 113.7 C and boiling point 184.3 C for a substance composed of such large atoms. The larger the atom or molecule, the stronger the London dispersion forces, so iodine has higher melting and boiling points than other halogens like fluorine and chlorine, but lower than those of metals or compounds with stronger intermolecular forces like ionic or hydrogen bonding.