Validation of X‐ray Wavefunction Refinement

Abstract

What is the most significant result of this study?This study showst hat in quantumc rystallography (QCr) an amalgamationb etweent heory and experiment leads to improvedp roperties. These geometrico re lectron-density properties are in better agreement with the measured data and simultaneously with benchmarking high-level theory than alternative methods that model the X-ray diffraction data. In fact, the reason for being in better agreement with the experiment is that more sophisticated theory is used in the modeling. It is important to realizet hat it is not ac ontradiction that more theory leads to better agreement with the experiment, but it is the very nature of the modeling process. Astudy that validates X-ray wavefunction refinement (XWR) as aQ Cr technique for modeling X-ray diffraction data was missingu ntil now.F rom now on it is not only ac laim anymore that QCr methods are a moderna lternative to established multipole or independent atom models of X-ray diffraction data analysis. Did serendipity play apart in this work?In this study,s erendipity did not play any role. The study had been planned over years and was designed to fulfil the purpose of validating X-ray wavefunction refinement. Te st compounds and data sets werer ationally selected to cover ar ange from lower quality to highest quality data to probe the performance of the methods compared. In place of serendipity, perseveranceo ft he first authorD r. Woinska played an important role in finishing the study,w hich generateda ne normousThe front cover artwork is provided by the group of Prof. Krzysztof Woźniak, Dr.P aulina M. Dominiak, and Dr.M agdalena Woiń ska. The image showsX -ray wavefunction refinement as am ethod of electrond ensity reconstruction (symbolized by a jigsaw puzzle), which allows to obtain accurate and precise molecular geometries as wella sp ropertieso fe lectrond ensity, and to perform data quality evaluations. Read the full text of the article at

Similarities and Differences between Crystal and Enzyme Environmental Effects on the Electron Density of Drug Molecules

“…Ac omparison with Figure S7 in the Supporting Information shows, however,t hat the multipole model using both the experimental and theoretically generated structure factorsleads to hugelydifferent resultsofthe Laplacian in this polar covalent CÀNb ond, and relative to that result the XCW fitting modela greesw ell with the theoretical models(compare ar elatedd iscussion in ref. [42] ).…”

Quantum Crystallography: Current Developments and Future Perspectives

“…Nevertheless, the multipole model can provide a charge density model as good as a double‐zeta basis‐set representation, is mature and its application is fast. Moreover, unlike in X‐ray wavefunction refinement,, the extracted experimental information can be easily identified and the danger to “get what you put in” is smaller (“in data we trust”) …”

Nine questions on energy decomposition analysis

“…Aside from valiant efforts toward X‐ray constrained wavefunctions, which might move all EDA's closer to experiment, most of what we do in the field requires a quantum mechanical calculation to approximate a wave function or density. My personal preference is toward concepts and quantities that are, at least in principle, experimentally measurable.…”