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Observation of the influence of dipolar and spin frustration effects on the magnetocaloric properties of a trigonal prismatic {Gd₇} molecular nanomagnet.

ABSTRACT: We report the synthesis and structure of a molecular {Gd₇} cage of the formula (ⁱPr₂NH₂)₆[Gd₇(?₃-OH)₃(CO₃)₆(O₂C ^t Bu)₁₂] which has crystallographic C_3h symmetry. Low temperature specific heat and adiabatic demagnetization experiments (the latter achieving temperatures below 100 mK), lead to the observation of the effects of both intramolecular dipolar interactions and geometric spin frustration. The dipolar interaction leads to a massive rearrangement of energy levels such that specific heat and entropy below 2 K are strongly modified while magnetic susceptibility and magnetization above 2 K are not affected. The consequences of these phenomena for low temperature magnetocaloric applications are discussed.

SUBMITTER: Pineda EM

PROVIDER: S-EPMC6016719 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Observation of the influence of dipolar and spin frustration effects on the magnetocaloric properties of a trigonal prismatic {Gd7} molecular nanomagnet.

Pineda Eufemio Moreno EM Lorusso Giulia G Zangana Karzan H KH Palacios Elias E Schnack Jürgen J Evangelisti Marco M Winpenny Richard E P REP McInnes Eric J L EJL

Chemical science 20160425 8

We report the synthesis and structure of a molecular {Gd7} cage of the formula (iPr2NH2)6[Gd7(μ3-OH)3(CO3)6(O2C t Bu)12] which has crystallographic C3h symmetry. Low temperature specific heat and adiabatic demagnetization experiments (the latter achieving temperatures below 100 mK), lead to the observation of the effects of both i ...[more]

PMID: 30155137

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