text: To estimate the surface energy of a pure, uniform material, an individual region of the material can be modeled as a cube. In order to move a cube from the bulk of a material to the surface, energy is required. This energy cost is incorporated into the surface energy of the material, which is quantified by:
  where  and  are coordination numbers corresponding to the surface and the bulk regions of the material, and are equal to 5 and 6, respectively;  is the surface area of an individual molecule, and  is the pairwise intermolecular energy.
  Surface area can be determined by squaring the cube root of the volume of the molecule:
  Here,  corresponds to the molar mass of the molecule,  corresponds to the density, and  is the Avogadro constant.
  In order to determine the pairwise intermolecular energy, all intermolecular forces in the material must be broken. This allows thorough investigation of the interactions that occur for single molecules. During sublimation of a substance, intermolecular forces between molecules are broken, resulting in a change in the material from solid to gas. For this reason, considering the enthalpy of sublimation can be useful in determining  the pairwise intermolecular energy. Enthalpy of sublimation can be calculated by the following equation:
  Using empirically tabulated values for enthalpy of sublimation, it is possible to determine the pairwise intermolecular energy. Incorporating this value into the surface energy equation allows for the surface energy to be estimated.
  The following equation can be used as a reasonable estimate for surface energy: