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On the Nature of the Bonding in Coinage Metal Halides.

ABSTRACT: This article analyzes the nature of the chemical bond in coinage metal halides using high-level ab initio Valence Bond (VB) theory. It is shown that these bonds display a large Charge-Shift Bonding character, which is traced back to the large Pauli pressure arising from the interaction between the bond pair with the filled semicore d shell of the metal. The gold-halide bonds turn out to be pure Charge-Shift Bonds (CSBs), while the copper halides are polar-covalent bonds and silver halides borderline cases. Among the different halogens, the largest CSB character is found for fluorine, which experiences the largest Pauli pressure from its σ lone pair. Additionally, all these bonds display a secondary but non-negligible π bonding character, which is also quantified in the VB calculations.

SUBMITTER: Đorđevic S

PROVIDER: S-EPMC8780489 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Nature of Alkali- and Coinage-Metal Bonds versus Hydrogen Bonds.

Project description:We have quantum chemically studied the structure and nature of alkali- and coinage-metal bonds (M-bonds) versus that of hydrogen bonds between A-M and B- in archetypal [A-M⋅⋅⋅B]- model systems (A, B=F, Cl and M=H, Li, Na, Cu, Ag, Au), using relativistic density functional theory at ZORA-BP86-D3/TZ2P. We find that coinage-metal bonds are stronger than alkali-metal bonds which are stronger than the corresponding hydrogen bonds. Our main purpose is to understand how and why the structure, stability and nature of such bonds are affected if the monovalent central atom H of hydrogen bonds is replaced by an isoelectronic alkali- or coinage-metal atom. To this end, we have analyzed the bonds between A-M and B- using the activation strain model, quantitative Kohn-Sham molecular orbital (MO) theory, energy decomposition analysis (EDA), and Voronoi deformation density (VDD) analysis of the charge distribution.

| S-EPMC7898866 | biostudies-literature

Nature of Metal-Drug Bond in Some Antitumor Active Complexes of Coinage Metal Ions.

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| S-EPMC7594011 | biostudies-literature

N-Heterocyclic carbenes on close-packed coinage metal surfaces: bis-carbene metal adatom bonding scheme of monolayer films on Au, Ag and Cu.

Project description:By means of scanning tunnelling microscopy (STM), complementary density functional theory (DFT) and X-ray photoelectron spectroscopy (XPS) we investigate the binding and self-assembly of a saturated molecular layer of model N-heterocyclic carbene (NHC) on Cu(111), Ag(111) and Au(111) surfaces under ultra-high vacuum (UHV) conditions. XPS reveals that at room temperature, coverages up to a monolayer exist, with the molecules engaged in metal carbene bonds. On all three surfaces, we resolve similar arrangements, which can be interpreted only in terms of mononuclear M(NHC)2 (M = Cu, Ag, Au) complexes, reminiscent of the paired bonding of thiols to surface gold adatoms. Theoretical investigations for the case of Au unravel the charge distribution of a Au(111) surface covered by Au(NHC)2 and reveal that this is the energetically preferential adsorption configuration.

| S-EPMC5858017 | biostudies-literature

Thermally Activated Delayed Fluorescence Coinage Metal Cluster Scintillator.

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Asymmetrically Substituted Phospholes as Ligands for Coinage Metal Complexes.

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| S-EPMC9182544 | biostudies-literature

Hetero-bimetallic Lanthanide-Coinage Metal Compounds Featuring Possible Metal-Metal Interactions in the Excited State.

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| S-EPMC8597103 | biostudies-literature

N-Heterocyclic Silylenes as Ligands in Transition Metal Carbonyl Chemistry: Nature of Their Bonding and Supposed Innocence.

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| S-EPMC7497151 | biostudies-literature

Synthesis and Properties of "Sandwich" Diimine-Coinage Metal Ethylene Complexes.

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| S-EPMC5019172 | biostudies-literature

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| S-EPMC7317956 | biostudies-literature

Enhanced Charge Transfer from Coinage Metal Doped InP Quantum Dots.

Project description:This paper describes coinage-metal-doped InP quantum dots (QDs) as a platform for enhanced electron transfer to molecular acceptors relative to undoped QDs. A synthetic strategy is developed to prepare doped InP/ZnSe QDs. First-principles DFT calculations show that Ag+ and Cu+ dopants localize photoexcited holes while leaving electrons delocalized. This charge carrier wave function modulation is leveraged to enhance electron transfer to molecular acceptors by up to an order of magnitude. Examination of photoluminescence quenching data suggests that larger electron acceptors, such as anthraquinone and methyl viologen, bind to the QD surface in two ways: by direct adsorption to the surface and by adsorption following displacement of a weakly bound surface cation-ligand complex. Reactions with larger acceptors show the greatest increases in electron transfer between doped and undoped quantum dots, while smaller acceptors show smaller enhancements. Specifically, benzoquinone shows the smallest, followed by naphthoquinone and then methyl viologen and anthraquinone. These results demonstrate the benefits of dopant-induced excited-state carrier localization on photoinduced charge transfer and highlight design principles for improved implementation of quantum dots in photoredox catalysis.

| S-EPMC10740119 | biostudies-literature

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