title: Improvement of anisotropic displacement parameters from invariom-model refinements for three L-hydroxylysine structures.
abstract: Three L-hydroxylysine structures have been determined at 100 K by single-crystal X-ray diffraction. High-resolution data using either a laboratory or synchrotron source were collected and subjected to invariom- and independent atom-model (IAM) refinements. Anisotropic displacement parameters (ADPs) obtained from invariom refinement were compared (i) with results from a full multipole and (ii) with an IAM high-order refinement. Differences were visualized with the program PEANUT and were complemented by quantitative results from a Hirshfeld test. Influences of scale factor differences, and of refinement against F;2 versus F, have been investigated. Systematic errors were observed in the IAM, especially when only low-order data were available. Although these errors were reduced in high-order IAM refinements, they only disappeared in charge density--and likewise--invariom refinements.
authors.affiliation: Institut für Anorganische Chemie der Universität Göttingen, Tammannstrasse 4, Göttingen, D 37077, Germany. bdittri@gwdg.de
authors.forename: B
authors.initials: B
authors.lastname: Dittrich
authors.forename: J J
authors.initials: JJ
authors.lastname: McKinnon
authors.forename: J E
authors.initials: JE
authors.lastname: Warren
mesh_terms: D016880:Anisotropy; D018360:Crystallography, X-Ray; D006901:Hydroxylysine / Q000031:analogs & derivatives* / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D006901:Hydroxylysine