Absolute configuration directly determined from 3D electron diffraction data

Abstract

Multiple scattering in 3D electron diffraction (3D ED) experiments is responsible for deviations of diffracted intensities from intensities expected from kinematical diffraction theory [1]. Though this is usually considered a disturbing factor in routine structure determinations, these deviations also contain valuable information on the absolute structure [2]. Analysing 3D ED measurements from different laboratories around the world, we demonstrate that the absolute structure of single submicrometric crystals can be reliably and easily determined in a routine way if dynamical diffraction effects are incorporated in the refinement of the structure model.

Argentotetrahedrite-(Cd), Ag6(Cu4Cd2)Sb4S13, a new member of the tetrahedrite group from Rudno nad Hronom, Slovakia.

“…The data collection was automated by the in-house software, including the tracking of the crystal following the procedure described by Plana-Ruiz et al (2020). Continuous-rotation 3D ED data (cRED) reduction was performed using the computer program PETS2 (Palatinus et al, 2019;Klar et al, 2021). The specific data processing for cRED data used in the structure solution and the refinement is extensively detailed in Klar et al (2021).…”

“…Continuous-rotation 3D ED data (cRED) reduction was performed using the computer program PETS2 (Palatinus et al, 2019;Klar et al, 2021). The specific data processing for cRED data used in the structure solution and the refinement is extensively detailed in Klar et al (2021). It includes the introduction of overlapping virtual frames (OVF) for the dynamical refinement that aims to model experimental intensities from continuous rotation data by summing consecutive experimental diffraction patterns into a set of virtual frames.…”

“…(2020). Continuous-rotation 3DED data (cRED) reduction was performed using the computer program PETS2 (Palatinus et al ., 2019; Klar et al ., 2021). The specific data processing for cRED data used in the structure solution and the refinement is extensively detailed in Klar et al .…”

“…The data reduction for the structure solution leads to an hkl-type file with R int (obs/all) = 0.1532/0.1570 and 100% coverage for sinθ/λ = 0.72 Å -1 . For the dynamical refinement, another hkl-type file is generated where each OVF is considered independent in the refinement (Palatinus et al, 2015a(Palatinus et al, , 2015bKlar et al, 2021). The structure was solved using Superflip (Palatinus and Chapuis, 2007;Palatinus, 2013) in Jana2006 (Petříček et al, 2014) and refined using DYNGO and Jana2006.…”