title: Spin crossover in iron(II) complexes with ferrocene-bearing triazole-pyridine ligands.
abstract: In the search for new multifunctional spin crossover molecular materials, here we describe the synthesis, crystal structures and magnetic and photomagnetic properties of the complexes trans-[Fe(Fc-tzpy)2(NCX)2]·CHCl3 where Fc-tzpy is the ferrocene-appended ligand 4-(2-pyridyl)-1H-1,2,3-triazol-1-ylferrocene, X = S (1) and X = Se (2). Both complexes display thermal- and light-induced (LIESST) spin crossover properties characterised by T1/2 = 85 and 168 K, ΔS = 55 and 66 J K(-1) mol(-1), ΔH = 4.7 and 11.1 kJ mol(-1) and TLIESST = 47 K and 39 K for1 and 2 respectively. The crystal structure of 1 and 2 measured at 275 K is consistent with the iron(ii) ion in the high-spin state while the crystal structure of at 120 K denotes the occurrence of complete transformation to the low-spin state.
authors.affiliation: Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, 46980 Paterna, Valencia, Spain. jose.a.real@uv.es.
authors.forename: Tania
authors.initials: T
authors.lastname: Romero-Morcillo
authors.affiliation: Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, 46980 Paterna, Valencia, Spain. jose.a.real@uv.es.
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Valverde-Muñoz
authors.affiliation: Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, 46980 Paterna, Valencia, Spain. jose.a.real@uv.es.
authors.forename: Lucía
authors.initials: L
authors.lastname: Piñeiro-López
authors.affiliation: Departamento de Física Aplicada, Universitat Politècnica de València, 46022, Valencia, Spain.
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Muñoz
authors.affiliation: Departamento de Química Orgánica, Facultad de Química, Campus de Espinardo, Universidad de Murcia, E-30100 Murcia, Spain.
authors.forename: Tomás
authors.initials: T
authors.lastname: Romero
authors.affiliation: Departamento de Química Orgánica, Facultad de Química, Campus de Espinardo, Universidad de Murcia, E-30100 Murcia, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Molina
authors.affiliation: Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, 46980 Paterna, Valencia, Spain. jose.a.real@uv.es.
authors.forename: José A
authors.initials: JA
authors.lastname: Real