MoPro is a cristallographic least square refinement package allowing structural or charge density studies of cristal stuctures of variable sizes, ranging from small molecules to biological macromolecules.
It implements spherical and non spherical, multipolar model of atomic electron density, the latter being necessary to take into account the deformation of electron density arising from interatomic interactions, which becomes visible and quantifiable at subatomic resolution.

Deformation electron density in the plane of a peptide bond of the 0.62Å resolution RD1 antifreeze protein.

Its complementary program VMoPro allows the computation of derived properties based on the multipolar formalism, as molecular electrostatic potential, topological properties or intermolecular interaction énergies.
MoPro and VMoPro are interfaced with the experimental multipolar database, which groups the multipolar parameters necessary to describe the charge density of common protein chemical groups. hence, the transfer of these parameters allows to compute derived electrostatic properties of biological macromolecules obtained at atomic resolution only.