Multicenter (FX)n/NH3 halogen bonds (X = Cl, Br and n = 1–5). QTAIM descriptors of the strength of the X…N interaction

• Autores: Buralli, Gabriel Jesús; Petelski, André N.; Peruchena, Nélida María; Sosa, Gladis Laura; Duarte, Darío Jorge Roberto
• Año de publicación: 2017
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Molecules, 2017, vol. 22, no. 11, p. 1-14.
• Materia: Halogen bond; Covalence; Multiple bonds; QTAIM; IQA scheme
• Institución: Universidad Nacional del Nordeste

Fil: Buralli, Gabriel Jesús. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina.
Fil: Petelski, André N. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina.
Fil: Petelski, André N. Universidad Tecnológica Nacional. Facultad Regional Resistencia; Argentina.
Fil: Peruchena, Nélida María. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina.
Fil: Sosa, Gladis Laura. Universidad Tecnológica Nacional. Facultad Regional Resistencia; Argentina.
Fil: Duarte, Darío Jorge Roberto. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina.
In the present work an in depth deep electronic study of multicenter XBs (FX)n/NH3 (X = Cl, Br and n = 1–5) is conducted. The ways in which X X lateral contacts affect the electrostatic or covalent nature of the X N interactions are explored at the CCSD(T)/aug-cc-pVTZ level and in the framework of the quantum theory of atoms in molecules (QTAIM). Calculations show that relatively strong XBs have been found with interaction energies lying between 41 and 90 kJ mol1 for chlorine complexes, and between 56 and 113 kJ mol1 for bromine complexes. QTAIM parameters reveal that in these complexes: (i) local (kinetics and potential) energy densities measure the ability that the system has to concentrate electron charge density at the intermolecular X N region; (ii) the delocalization indices [ (A,B)] and the exchange contribution [VEX(X,N)] of the interacting quantum atoms (IQA) scheme, could constitute a quantitative measure of the covalence of these molecular interactions; (iii) both classical electrostatic and quantum exchange show high values, indicating that strong ionic and covalent contributions are not mutually exclusive.