Improving the scattering-factor formalism in protein refinement: application of the University at Buffalo Aspherical-Atom Databank to polypeptide structures

Application of the University at Buffalo theoretical databank of aspherical pseudoatoms to the refinement of experimental X-ray data from polypeptide structures significantly improves the resulting molecular geometries, residual Fourier difference maps, atomic anisotropic displacement parameters and phases of reflections. Implications for the refinement of protein data are discussed.