J. Appl. Cryst. (2010), 43, 1100-1107. [ doi:10.1107/S0021889810025598 ]
Because they scatter X-rays weakly, H atoms are often abused or neglected during structure refinement. The reasons why the H atoms should be included in the refinement and some of the consequences of mistreatment are discussed along with selected real examples demonstrating some of the features for hydrogen treatment that can be found in the software suite CRYSTALS.