X-ray diffraction and QTAIM calculations of the non-covalent intermolecular fluorine-fluorine interactions in tris(trifluoroacetylacetonato)-manganese(III)

An X-ray study was conducted on tris(trifluoroacetylacetonato)-manganese(III). The two different molecules in the unit cell exhibit a distorted octahedral geometry and moderate compression Jahn–Teller distortion respectively. A number of F⋯H and F⋯F intermolecular interactions were observed in the packing of the crystals in the solid state. The crystal packing effects could lead to the observed compressed Jahn–Teller distortion, instead of the expected elongation Jahn–Teller distortion. A Quantum Theory of Atoms in Molecules (QTAIM) study on selected molecular pairs identified intermolecular bond paths (BP) between fluorine atoms with bond critical points (BCP) which have positive electron density (ρ) and Laplacian of electron density (∇2ρ) values, which are indicative of weak F···F non-covalent bonding interactions.