title: Ligand effects due to resonance character in LAuCCH(-) (L = F, Cl, Br, I, CCH) complexes: an NBO/NRT analysis.
abstract: The organogold complexes of LAuCCH(-) (L = F, Cl, Br, I, CCH) were investigated using natural bond orbital/natural resonance theory (NBO/NRT) methods. The NBO/NRT results strongly support the general resonance-type three-center-four-electron (3c/4e) picture of LAuCCH: L(-): Au-CCH ↔ L-Au :CCH(-), arising from hyperconjugation interactions. The sums of ionic and covalent contributions to both L-Au and Au-CCH bonds are all slightly larger than that due to the additional π-back bonding within the 3c/4e hyperbonded triad. This complementary relationship between L-Au and Au-CCH bond orders implies a competing relationship between the ancillary ligand and CCH around the gold atom. We discuss the ligand effects in the LAuCCH(-) series on the basis of this competing relationship.
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Normal University, Wenhua East Road 88, Jinan, Shandong, 250014, People's Republic of China, gqzhang@sdnu.edu.cn.
authors.forename: Guiqiu
authors.initials: G
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Huanjing
authors.initials: H
authors.lastname: Yue
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Shengnan
authors.initials: S
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Fu