title: Co-crystallized cis and trans isomers of dichlorobis(2-picolylamine)iron(II).
abstract: The octahedral cis and trans isomers of dichlorobis(2-picolylamine)iron(II), [FeCl2(C6H8N2)2], co-crystallize in a 1:1 ratio. The cis isomer lies on a twofold axis, whereas the trans isomer lies on an inversion centre. The structure is fully ordered, with both Fe atoms in a pure high-spin state. The Fe, Cl and N(H2) atoms of both isomers lie in the same plane, allowing all Cl and amine H atoms to be engaged in extensive two-dimensional hydrogen bonding. The hydrogen-bonded layers are interconnected through pi-pi interactions between the pyridine rings. Searches in the Cambridge Structural Database uncover very few examples of such isomer co-existence.
authors.affiliation: Department of Chemistry, University of Bergen, Allégt. 41, 5007 Bergen, Norway. karl.tornroos@kj.uib.no
authors.forename: Karl W
authors.initials: KW
authors.lastname: Törnroos
authors.forename: Dmitry
authors.initials: D
authors.lastname: Chernyshov
authors.forename: Marc
authors.initials: M
authors.lastname: Hostettler
authors.forename: Hans Beat
authors.initials: HB
authors.lastname: Bürgi