Anion–Anion Interactions in Aerogen-Bonded Complexes. Influence of Solvent Environment
Anna Grabarz, Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner
Abstract
Ab initio calculations are applied to the question as to whether a AeX5− anion (Ae = Kr, Xe) can engage in a stable complex with another anion: F−, Cl−, or CN−. The latter approaches the central Ae atom from above the molecular plane, along its C5 axis. While the electrostatic repulsion between the two anions prevents their association in the gas phase, immersion of the system in a polar medium allows dimerization to proceed. The aerogen bond is a weak one, with binding energies less than 2 kcal/mol, even in highly polar aqueous solvent. The complexes are metastable in the less polar solvents THF and DMF, with dissociation opposed by a small energy barrier.
Topics & Concepts
ChemistryIonSolventMetastabilityPolarDissociation (chemistry)Aqueous solutionCrystallographyAb initio quantum chemistry methodsBinding energyAtom (system on chip)Computational chemistryMoleculeInorganic chemistryChemical physicsPhysical chemistryOrganic chemistryAtomic physicsEmbedded systemAstronomyPhysicsComputer scienceAdvanced Chemical Physics StudiesCrystallography and molecular interactionsFluorine in Organic Chemistry