Statistical analysis of multipole-model-derived structural parameters and charge-density properties from high-resolution X-ray diffraction experiments

A comprehensive analysis of various properties derived from multiple high-resolution X-ray diffraction experiments is reported. The study indicates the precision and reliability of the analysed quantities and their usefulness in charge-density studies of organic molecules.

Hirshfeld atom refinement for modelling strong hydrogen bonds

Different X-ray refinement methods for modelling hydrogen bonds in the compound L-phenylalaninium hydrogen maleate are compared. It is found that Hirshfeld atom refinement (HAR) produces bond lengths involving hydrogen atoms in agreement with benchmarking results from neutron diffraction, and it is the only X-ray method to obtain a symmetric hydrogen site in the intramolecular hydrogen bond of this compound. Residual-density distributions in HAR are better than in the multipole-based models.