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An Effectively Uncoupled Gd₈ Cluster Formed through Fixation of Atmospheric CO₂ Showing Excellent Magnetocaloric Properties.

ABSTRACT: The [Gd₈(opch)₈(CO₃)₄(H₂O)₈]·4H₂O·10MeCN coordination cluster (1) crystallises in P1¯. The Gd₈ core is held together by four bridging carbonates derived from atmospheric CO₂ as well as the carboxyhydrazonyl oxygens of the 2-hydroxy-3-methoxybenzylidenepyrazine-2-carbohydrazide (H₂opch) Schiff base ligands. The magnetic measurements show that the Gd^III ions are effectively uncoupled as seen from the low Weiss constant of 0.05 K needed to fit the inverse susceptibility to the Curie-Weiss law. Furthermore, the magnetisation data are consistent with the Brillouin function for eight independent Gd^III ions. These features lead to a magnetocaloric effect with a high efficiency which is 89% of the theoretical maximum value.

SUBMITTER: Braun J

PROVIDER: S-EPMC10779177 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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An Effectively Uncoupled Gd8 Cluster Formed through Fixation of Atmospheric CO2 Showing Excellent Magnetocaloric Properties.

Braun Jonas J Seufert Daniel D Anson Christopher E CE Tang Jinkui J Powell Annie K AK

International journal of molecular sciences 20231223 1

The [Gd8(opch)8(CO3)4(H2O)8]·4H2O·10MeCN coordination cluster (1) crystallises in P1¯. The Gd8 core is held together by four bridging carbonates derived from atmospheric CO2 as well as the carboxyhydrazonyl oxygens of the 2-hydroxy-3-methoxybenzylidenepyrazine-2-carbohydrazide (H2opch) Schiff base ligands. The magnetic measurements show that the GdIII ions are effective ...[more]

PMID: 38203439

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