Multicenter (FX)n/NH3 Halogen Bonds (X = Cl, Br and n = 1-5). QTAIM Descriptors of the Strength of the XâââN Interaction.
Molecules
; 22(11)2017 Nov 22.
Article
em En
| MEDLINE
| ID: mdl-29165403
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 XâââX lateral contacts affect the electrostatic or covalent nature of the XâââN 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 mol-1 for chlorine complexes, and between -56 and -113 kJ mol-1 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 XâââN region; (ii) the delocalization indices [δ(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.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Halogênios
Tipo de estudo:
Clinical_trials
Idioma:
En
Revista:
Molecules
Assunto da revista:
BIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Argentina
País de publicação:
Suíça