title: Coordination complexes of 4-methylimidazole with ZnIIand CuIIin gas phase and in water: a DFT study.
abstract: A quantum chemistry study of mononuclear metal coordination with four 4-methylimidazole ligands (4-MeIm) was investigated. The four complexes [Cu(4-MeIm)4]2+, [Cu(4-MeIm)4, H2O]2+, [Zn(4-MeIm)4]2+and [Zn(4-MeIm)4, H2O]2+were studied with particular attention to the Nπ or Nτ possible coordinations of the 4-MeIm ring with the metals, using different DFT methods. The results suggest that the Nτ coordination of 4-MeIm ring to ZnIIor CuIIis more favorable whatever the level of calculation. In contrast, the addition of one water molecule in the first coordination sphere of the metal ions provides five-coordinated complexes showing no Nπ or Nτ preferences. There is good agreement between the DFT-calculated structure and those available experimentally. When metal ions are four-fold coordinated, they adopt a tetrahedral geometry. When CuIIand ZnIIare five-fold coordinated, highly symmetric structures or intermediate structures are calculated. Similar energies are calculated for different structures, suggesting flat potential energy surfaces. The addition of implicit solvent modifies the calculated first coordination sphere, especially for [Cu(4-MeIm)4, H2O]2+structures. The QTAIM and ELF topological analyses of the interaction between CuIIand the neutral ligands, clearly indicate a dative bonding with a strong ionic character.
authors.affiliation: Departement de Physique Laboratoire de Physique de la Matière Condensée (LPMC) Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire 2092, Tunis, Tunisia.|Institut Charles Gerhardt, MACS, UMR 5253 CNRS-ENSCM-UM, 8 rue de l'Ecole Normale, 34296, Montpellier Cedex 5, France.
authors.forename: Malek
authors.initials: M
authors.lastname: Boukallaba
authors.affiliation: Departement de Physique Laboratoire de Physique de la Matière Condensée (LPMC) Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire 2092, Tunis, Tunisia.|Université de la Manouba, Institut Supérieur des Arts Multimédia de la Manouba, 2010, la Manouba, Tunisia.
authors.forename: Boutheïna
authors.initials: B
authors.lastname: Kerkeni
authors.affiliation: CNRS, LCC (Laboratoire de Chimie de Coordination), 205, route de Narbonne, BP 44099, 31077, Toulouse Cedex 4, France.|Université de Toulouse, UPS, INPT, 31077, Toulouse Cedex 4, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Lepetit
authors.affiliation: Institut Charles Gerhardt, MACS, UMR 5253 CNRS-ENSCM-UM, 8 rue de l'Ecole Normale, 34296, Montpellier Cedex 5, France. dorothee.berthomieu@enscm.fr.|LPCNO, UMR 5215 CNRS-INSA-UPS, 135 avenue de Rangueil, 31077, Toulouse Cedex 4, France. dorothee.berthomieu@enscm.fr.
authors.forename: Dorothée
authors.identifier: http://orcid.org/0000-0002-3818-105X
authors.initials: D
authors.lastname: Berthomieu
keywords: 4-methylimidazole and water; Coordination complexes with ZnII or CuII; DFT; ELF topological analyses; Histidine; Implicit solvents; QTAIM