Communication: Evidence of halogen bonds in clathrate cages.
We present a theoretical characterization of the interaction of Cl2and Br2in the 512and 51262clathrate cages, respectively, based on energy partitioning analysis and a study of the electronic shifts associated with transitions to the main valence bands. Our analysis clearly shows that while Br2@51262does not show halogen bonding interactions in its equilibrium geometry, Cl2@512presents all the characteristics expected for halogen bonding. This is accomplished by the interaction of the usual sigma-hole with the lone pair of the closest oxygen atom involved in hydrogen bonding within the cage framework, though breaking of the hydrogen bond is not required. This possibility, which had not been considered in previous analyses, opens up a new way of looking at the interactions of dihalogens with the nearest water molecules in the cage.
Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, México.
David
D
Ochoa-Resendiz
Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, México.
Fidel A
FA
Batista-Romero
Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, México.
Ramón
R
Hernández-Lamoneda