Frontispiece: From the {Fe<sup>III</sup><sub>2</sub>Ln<sub>2</sub>} Butterfly's Perspective: the Magnetic Benefits and Challenges of Cooperativity within 3 d–4 f Based Coordination Clusters.
Frontispiece: From the {FeIII2Ln2} Butterfly's Perspective: the Magnetic Benefits and Challenges of Cooperativity within 3 d-4 f Based Coordination Clusters Cooperativity, Iron, lanthanides, Mössbauer spectroscopy, molecular magnetism Keywords: cooperativity; Iron; lanthanides; Mössbauer spectroscopy; molecular magnetism EN cooperativity Iron lanthanides Mössbauer spectroscopy molecular magnetism 1 1 1 11/05/21 20211102 NES 211102 The huge variety of species on earth results from its dynamic iron-based magnetic core.