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Updated: Jul 4, 2026

Modeling Ligands into Maps Derived from Electron Cryomicroscopy
Published on: July 19, 2024
Crystal structure and chemical bonding of Mg3Ru2
Rainer Pöttgen1, Viktor Hlukhyy, Aleksey Baranov
1Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstrasse 30, 48149 Münster, Germany. pottgen@uni-muenster.de
Abstract:
Mg 3Ru 2 was prepared by a reaction between the elements in the ideal ratio in a sealed tantalum ampule. Its beta-manganese type crystal structure was refined on the basis of the single-crystal data: space group P4 132, a = 693.52(6) pm, wR2 = 0.024, 168 F (2) values, and 10 parameters. The magnesium (CN = 14) and ruthenium (CN = 12) atoms are completely ordered on the 12d and 8c sites of the crystal structure of beta-manganese. Both environments can be considered as Frank-Kasper related polyhedra. A periodic nodal surface P4 132(110) pi (1) P4 132 separates the magnesium and ruthenium positions in two different labyrinths, suggesting different chemical interactions within different parts of the structural motif. Analysis of the chemical bonding with the electron localizability indicator (ELI-D) reveals covalently interacting three-bonded ruthenium atoms, forming a 3D network. The network interacts with the magnesium substructure by multicenter bonds.
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