• Jakobsen, Vibe Boel
• Morgan, Grace
• Carpenter, Michael
• Felton, Solveig
• Trzop, Elzbieta
• Esien, Kane
• Müllerbunz, Helge
• Collet, Eric
• Dobbelaar, Emiel

Abstract

<jats:title>Abstract</jats:title><jats:p>A Mn<jats:sup>III</jats:sup> spin crossover complex with atypical two‐step hysteretic thermal switching at 74 K and 84 K shows rich structural–magnetic interplay and magnetic‐field‐induced spin state switching below 14 T with an onset below 5 T. The spin states, structures, and the nature of the phase transitions are elucidated via X‐ray and magnetization measurements. An unusual intermediate phase containing four individual sites, where <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/anie202114021-math-0001.png" xlink:title="urn:x-wiley:14337851:media:anie202114021:anie202114021-math-0001" />are in a pure low spin state, is observed. The splitting of equivalent sites in the high temperature phase into four inequivalent sites is due to a structural reorganization involving a primary and a secondary symmetry‐breaking order parameter that induces a crystal system change from orthorhombic→monoclinic and a cell doubling. Further cooling leads to a reconstructive phase transition and a monoclinic low‐temperature phase with two inequivalent low‐spin sites. The coupling between the order parameters is identified in the framework of Landau theory.</jats:p>

Topics

• impedance spectroscopy
• compound
• phase
• theory
• phase transition
• magnetization