Validation of X-ray wavefunction refinement

DOI: 10.1002/cphc.201700810

Authors: Magdalena Woińska (University of Warsaw) , Dylan Jayatilaka (The University of Western Australia) , Birger Dittrich (Heinrich-Heine-Universitat Dusseldorf) , Ralf Flaig (Diamond Light Source) , Peter Luger (Freie Universitat Berlin) , Krzysztof Woźniak (University of Warsaw) , Paulina M. Dominiak (University of Warsaw) , Simon Grabowsky (Universitat Bremen)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Chemphyschem , VOL 56

State: Published (Approved)
Published: November 2017

Abstract: In this work, the quality of the electron density in crystals reconstructed by the multipolar model (MM) and by X-ray wavefunction refinement (XWR) is tested on a set of high-resolution X-ray diffraction data sets of four amino acids and six tripeptides. It results in the first thorough validation of XWR. Agreement statistics, figures of merit, residual- and deformation-density maps, as well as atomic displacement parameters are used to measure the quality of the reconstruction relative to the measured structure factors. Topological analysis of the reconstructed density is carried out to obtain atomic and bond-topological properties, which are subsequently compared to the values derived from benchmarking periodic DFT geometry optimizations. XWR is simultaneously in better agreement than the MM with both benchmarking theory and the measured diffraction pattern. In particular, the obvious problems with the description of polar bonds in the MM are significantly reduced by using XWR. Similarly, modeling of electron density in the vicinity of hydrogen atoms with XWR is visibly improved.

Journal Keywords: amino acids; quantum crystallography; electron density; quantum chemistry; X-ray diffraction

Subject Areas: Chemistry, Physics, Technique Development


Technical Areas:

Added On: 28/11/2017 09:35

Discipline Tags:

Physics Physical Chemistry Technique Development - Physics Chemistry

Technical Tags: