Analyzing Protein Structures by Canonical Distributions of Electrons
Recurring groups of atoms in molecules are surrounded by specific canonical distributions of electrons. Deviations from these distributions reveal unrealistic molecular geometries. The CanDen webservice combines canonical electron densities with classical electron densities derived from X-ray diffraction experiments to aid in the real space refinement of crystal structures. This combination generally yields superior molecular models with reduced excess electron densities and improved stereochemistry without compromising the agreement between molecular models and experimental data.