title: Novel CX⋯π halogen bonds in complexes of acetylene and its derivatives of Na and MPH3 (M=Cu, Ag, Au) with XCCF (X=Cl, Br, I).
abstract: Ab initio calculations have been carried out for a variety of model systems with a T-shaped CX⋯π motif. The CX⋯π interaction of acetylene with the halogen donor molecule XCCF (X=Cl, Br, I) is invariably found to be weak with the interaction energy less than 11kJ/mol in magnitude. Substitution of the two protons in acetylene with more electron-donating sodium atoms increases the π electron density in the CC bond and leads to a substantial enhancement in its interaction with the halogen donor. The calculated interaction energies increase to as much as 73kJ/mol in the case of C2Na2-ICCF. The interaction of XCCF with a model coinage metal ethynide, H3PMCCMPH3 (M=Cu, Ag, Au), is intermediate between these two extremes, and the interaction energy is related to the nature of coinage metals. The CX⋯π halogen bonds have been analyzed with natural bond orbital, atoms in molecules, and energy decomposition.
authors.affiliation: The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, People's Republic of China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhuo
authors.affiliation: The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, People's Republic of China.
authors.forename: Mingjuan
authors.initials: M
authors.lastname: Liu
authors.affiliation: The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, People's Republic of China. Electronic address: liqingzhong1990@sina.com.
authors.forename: Qingzhong
authors.initials: Q
authors.lastname: Li
authors.affiliation: The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, People's Republic of China.
authors.forename: Wenzuo
authors.initials: W
authors.lastname: Li
authors.affiliation: The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, People's Republic of China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Cheng
mesh_terms: D000114:Acetylene / Q000737:chemistry*; D006219:Halogens / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*
chemical_list: D006219:Halogens; D008670:Metals; D000114:Acetylene
keywords: Ab initio calculations; CX⋯π halogen bond; Coinage metal (I)-ethynide; Ethyne; Sodium acetylide