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Mg₃Pt₂: Anionic Chains in a Eu₃Ga₂-Type Structure.

ABSTRACT: The binary phase Mg₃Pt₂ was prepared by direct reaction between the elements or by spark-plasma synthesis starting with MgH₂ and PtCl₂. The compound crystallizes in the monoclinic space group C2/c with a = 7.2096(3) Å, b = 7.1912(4) Å, c = 6.8977(3) Å, and β = 106.072(3)° and is isotypic to Eu₃Ga₂. Analysis of the electron density within the quantum theory of atoms in molecules shows a significant charge transfer from Mg to Pt in agreement with the electronegativity difference. Further study of the chemical bonding with the electron localizability approach reveals the formation of Pt chains stabilized by a complex system of multicenter interactions involving Mg and Pt species. The metallic character of Mg₃Pt₂ is confirmed by electronic structure calculations and physical measurements.

SUBMITTER: Agnarelli L

PROVIDER: S-EPMC8424623 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Mg3Pt2: Anionic Chains in a Eu3Ga2-Type Structure.

Agnarelli Laura L Prots Yurii Y Burkhardt Ulrich U Schmidt Marcus M Koželj Primož P Leithe-Jasper Andreas A Grin Yuri Y

Inorganic chemistry 20210824 17

The binary phase Mg3Pt2 was prepared by direct reaction between the elements or by spark-plasma synthesis starting with MgH2 and PtCl2. The compound crystallizes in the monoclinic space group C2/c with a = 7.2096(3) Å, b = 7.1912(4) Å, c = 6.8977(3) Å, and β = 106.072(3)° and is isotypic to Eu3Ga2. Analysis of the electron density within the quantum theory of atoms in molecules shows a significan ...[more]

PMID: 34428036

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