Representation of Three-Center-Two-Electron Bonds in Covalent Molecules with Bridging Hydrogen Atoms

Autor/in	Parkin, Gerard
Titel	Representation of Three-Center-Two-Electron Bonds in Covalent Molecules with Bridging Hydrogen Atoms
Quelle	In: Journal of Chemical Education, 96 (2019) 11, S.2467-2475 (9 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Zusatzinformation	ORCID (Parkin, Gerard)
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0021-9584
Schlagwörter	Inorganic Chemistry; Molecular Structure; Molecular Biology; Identification; Nuclear Physics; Metallurgy + Suchen Sie Ihr Suchwort? Anorganische Chemie; Molekularbiologie; Identifikation; Identifizierung; Atomphysik; Kernphysik; Hüttenwesen
Abstract	Many compounds can be represented well in terms of the two-center-two-electron (2c-2e) bond model. However, it is well-known that this approach has limitations; for example, certain compounds require the use of three-center-two-electron (3c-2e) bonds to provide an adequate description of the bonding. Although a classic example of a compound that features a 3c-2e bond is provided by diborane, B[subscript 2]H[subscript 6], 3c-2e interactions also feature prominently in transition metal chemistry, as exemplified by bridging hydride compounds, agostic compounds, dihydrogen complexes, and hydrocarbon and silane [sigma]-complexes. In addition to being able to identify the different types of bonds (2c-2e and 3c-2e) present in a molecule, it is essential to be able to utilize these models to evaluate the chemical reasonableness of a molecule by applying the octet and 18-electron rules; however, to do so requires determination of the electron counts of atoms in molecules. Although this is easily achieved for molecules that possess only 2c-2e bonds, the situation is more complex for those that possess 3c-2e bonds. Therefore, this article describes a convenient approach for representing 3c-2e interactions in a manner that facilitates the electron counting procedure for such compounds. In particular, specific attention is devoted to the use of the half-arrow formalism to represent 3c-2e interactions in compounds with bridging hydrogen atoms. (As Provided).
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Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2020/1/01