| Autor: |
Dewar, Michael J. S., Dunitz, Jack D., Hafner, Klaus, Heilbronner, Edgar, Itô, Shô, Lehn, Jean-Marie, Niedenzu, Kurt, Raymond, Kenneth N., Rees, Charles W., Vögtle, Fritz, Clouthier, D. J., Corio, P. L., Epiotis, N. D., Jørgensen, C. K., Moule, D. C., Epiotis, Nicolaos D. |
| Zdroj: |
Relationships & Mechanisms in the Periodic Table; 1989, p47-166, 120p |
| Abstrakt: |
Interdisciplinary barriers separating the "organic", "inorganic" and "solid state" subdisciplines of chemistry exist because there is no conceptual apparatus which clearly delineates how the rules of bonding depend on the identity of the atoms comprising a molecule and how they change as we move from the domain to another. We present a theory which is based on a fusion of MO and VB concepts which enables one to do the following: Dissect a molecule into fragments, apportion the valence electrons in the fragment orbitals, and then make "bonds" connecting the fragments. In this way two key elements of the bonding problem become transparent:(a)The interplay between fragment excitation (investment) and "bond" making (return) in engendering net stabilization (profit) of the system.(b)The mechanism of bond-making. Nonmetals bind primarily by spin-pairing plus one-electron delocalization due to overlap while metals bind mainly by two-electron delocalization in which overlap is assisted by an overlap-independent mechamism of bonding. The recognition that the mode of electron delocation depends on the identity of an atom sets up the stage for a differentiation between structural and reactivity properties expected from organic and inorganic molecules. This point is illustrated by diverse applications and reference to existing experimental and computational data. The article itself can be viewed as a first step towards a reexamination of solid state physics phenomena (most notably conductivity and superconductivity) from a chemist's vantage point after it has been demonstrated that a self-consistent, qualitative understanding of molecular electronics across the Periodic Table is now at hand. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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