Anion-induced contraction of helical receptorsElectronic supplementary information (ESI) available: Ligand synthesis, crystal packing, table of weak interactions of the crystal structures and Jobs plot of the UV-Vis experiments. CCDC 719944 and 719945. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/b902772f

Uptake of a tetrafluoroborate anion into the centre of a dicopper bis-salicylaldoxime complex causes a major contraction of the cavity and an increase in helicity. [ABSTRACT FROM AUTHOR]