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Solvate crystals of [Fe<jats:sub>2<\/jats:sub>(\u03bc\u2212<jats:italic>L<\/jats:italic><jats:sup>1<\/jats:sup>)<jats:sub>2<\/jats:sub>][BF<jats:sub>4<\/jats:sub>]<jats:sub>4<\/jats:sub> exhibit three different helicate conformations, which differ in the torsions of their butanediyl linker groups. The solvates exhibit gradual thermal spin\u2010crossover, with examples of stepwise switching and partial spin\u2010crossover to a low\u2010temperature mixed\u2010spin form. Salts of [Fe<jats:sub>2<\/jats:sub>(\u03bc\u2212<jats:italic>L<\/jats:italic><jats:sup>2<\/jats:sup>)<jats:sub>2<\/jats:sub>]<jats:sup>4+<\/jats:sup> are high\u2010spin, which reflects their highly twisted iron coordination geometry. The composition and dynamics of assembly structures formed by iron(II) with <jats:italic>L<\/jats:italic><jats:sup>1<\/jats:sup>\u2212<jats:italic>L<\/jats:italic><jats:sup>3<\/jats:sup> vary with the ligand linker group, by mass spectrometry and <jats:sup>1<\/jats:sup>H NMR spectroscopy. Gas\u2010phase DFT calculations imply the butanediyl linker conformation in [Fe<jats:sub>2<\/jats:sub>(\u03bc\u2212<jats:italic>L<\/jats:italic><jats:sup>1<\/jats:sup>)<jats:sub>2<\/jats:sub>]<jats:sup>4+<\/jats:sup> influences its spin state properties, but show anomalies attributed to intramolecular electrostatic repulsion between the iron atoms.<\/jats:p>","DOI":"10.1002\/chem.202202578","type":"journal-article","created":{"date-parts":[[2022,11,16]],"date-time":"2022-11-16T04:53:50Z","timestamp":1668574430000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Di\u2010Iron(II) [2+2] Helicates of Bis\u2010(Dipyrazolylpyridine) Ligands: The Influence of the Ligand Linker Group on Spin State Properties"],"prefix":"10.1002","volume":"29","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3855-4530","authenticated-orcid":false,"given":"Rafal","family":"Kulmaczewski","sequence":"first","affiliation":[{"name":"School of Chemistry University of Leeds  Woodhouse Lane Leeds LS2 9JT UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isaac T.","family":"Armstrong","sequence":"additional","affiliation":[{"name":"School of Chemistry University of Leeds  Woodhouse Lane Leeds LS2 9JT UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3048-060X","authenticated-orcid":false,"given":"Pip","family":"Catchpole","sequence":"additional","affiliation":[{"name":"School of Chemistry University of Leeds  Woodhouse Lane Leeds LS2 9JT UK"},{"name":"Department of Chemistry Lancaster University  Lancaster LA1 4YB UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily S. 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