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Updated: May 17, 2026

Neutron Crystallography Data Collection and Processing for Modelling Hydrogen Atoms in Protein Structures
Published on: December 1, 2020
Experimental determination of spin-dependent electron density by joint refinement of X-ray and polarized neutron
Maxime Deutsch1, Nicolas Claiser, Sébastien Pillet
1Université de Lorraine Laboratoire de Cristallographie, Résonance Magnétique et Modélisations, UMR 7036 Vandoeuvre-lès-Nancy, F-54506 France.
Abstract:
New crystallographic tools were developed to access a more precise description of the spin-dependent electron density of magnetic crystals. The method combines experimental information coming from high-resolution X-ray diffraction (XRD) and polarized neutron diffraction (PND) in a unified model. A new algorithm that allows for a simultaneous refinement of the charge- and spin-density parameters against XRD and PND data is described. The resulting software MOLLYNX is based on the well known Hansen-Coppens multipolar model, and makes it possible to differentiate the electron spins. This algorithm is validated and demonstrated with a molecular crystal formed by a bimetallic chain, MnCu(pba)(H(2)O)(3)·2H(2)O, for which XRD and PND data are available. The joint refinement provides a more detailed description of the spin density than the refinement from PND data alone.
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