Linear-scaling aspherical crystallographic refinement of proteins: a case study for crambin and rubredoxin.

ABSTRACT: Hirshfeld atom refinement (HAR) provides a more realistic interpretation of crystallographic data than the standard independent atom model (IAM) by using aspherical atomic form factors derived from quantum mechanical (QM) calculations. With this aspherical description, it is possible to obtain improved atomic positions, atomic displacement parameters and correct bond lengths even for hydrogen atoms. Unfortunately, HAR is computationally very demanding for larger molecules. Recently, we suggested how this can be solved by calculating aspherical atomic form factors for small overlapping fragments of the system, the fragHAR approach. Here, we have created a new implementation of fragHAR in Olex2 within the NoSpherA2 interface. We have also solved previous issues with hydrogen bonds by automat

SUBMITTER: Bergmann J 

PROVIDER: S-EPMC12809447 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature