title: Compositional dependence of anomalous thermal expansion in perovskite-like ABX3 formates.
abstract: The compositional dependence of thermal expansion behaviour in 19 different perovskite-like metal-organic frameworks (MOFs) of composition [A(I)][M(II)(HCOO)3] (A = alkylammonium cation; M = octahedrally-coordinated divalent metal) is studied using variable-temperature X-ray powder diffraction measurements. While all systems show essentially the same type of thermomechanical response-irrespective of their particular structural details-the magnitude of this response is shown to be a function of A(I) and M(II) cation radii, as well as the molecular anisotropy of A(I). Flexibility is maximised for large M(II) and small A(I), while the shape of A(I) has implications for the direction of framework hingeing.
authors.affiliation: Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, UK. andrew.goodwin@chem.ox.ac.uk and Laboratory of Crystallography, University of Bayreuth, D-95440 Bayreuth, Germany.
authors.forename: Ines E
authors.initials: IE
authors.lastname: Collings
authors.affiliation: Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, UK. andrew.goodwin@chem.ox.ac.uk.
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Hill
authors.affiliation: Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, UK. andrew.goodwin@chem.ox.ac.uk.
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Cairns
authors.affiliation: Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, UK. andrew.goodwin@chem.ox.ac.uk.
authors.forename: Richard I
authors.initials: RI
authors.lastname: Cooper
authors.affiliation: Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, UK. andrew.goodwin@chem.ox.ac.uk.
authors.forename: Amber L
authors.initials: AL
authors.lastname: Thompson
authors.affiliation: Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK.
authors.forename: Julia E
authors.initials: JE
authors.lastname: Parker
authors.affiliation: Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK.
authors.forename: Chiu C
authors.initials: CC
authors.lastname: Tang
authors.affiliation: Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, UK. andrew.goodwin@chem.ox.ac.uk.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Goodwin