title: Guest-Activated Forbidden Tilts in a Molecular Perovskite Analogue.
abstract: The manipulation of distortions in perovskite structures is critical to tailoring the properties of these materials for a variety of applications. Here we demonstrate a violation of established octahedral tilt rules in the double perovskite analogue (NH4)2SrFe(CN)6·2H2O. The forbidden tilt pattern we observe arises through coupling to hydration-driven Jahn-Teller-like distortions of the Sr coordination environment. Access to novel distortion mechanisms and the ability to switch these distortions on and off through chemical modification fundamentally expands the toolbox of techniques available for engineering symmetry-breaking processes in solid materials.
authors.affiliation: Department of Chemistry, University of Oxford , Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, U.K.|School of Chemistry, University of Sydney , Sydney, NSW 2006, Australia.
authors.forename: Samuel G
authors.initials: SG
authors.lastname: Duyker
authors.affiliation: Department of Chemistry, University of Oxford , Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, U.K.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Hill
authors.affiliation: School of Engineering, University of Newcastle , Callaghan, NSW 2308, Australia.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Howard
authors.affiliation: Department of Chemistry, University of Oxford , Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, U.K.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Goodwin