1997 Polanyi Award Lecture: Why are there atoms in chemistry?
Article Abstract:
Not until Ernest Rutherford's nuclear model of the atom emerged was John Dalton vindicated for his bold assumption in the atomic hypothesis. He stated that atoms keep their masses and identities in chemical combination. In time chemists realized atoms have unique mass and characteristic additive properties. Even in a molecule they can be recognized; they help predict static and reactive properties of a molecule. In time Richard Feynman and Schwinger vindicated theoretically the model of a functional group as carrier of chemical information. Now an atom can be seen as an open quantum system. Renormalization can account for the nature of force, short range. It makes possible identification of a certain group regardless of environment. Proper open systems so predicted define an atom. The definition accounts for the retention of identity. Replacement of quantum mechanical force and energy observables is possible with real space density distributions. Forms of the distributions are parallel to the transferable topology in electron density distribution.
Publication Name: Canadian Journal of Chemistry
Subject: Chemistry
ISSN: 0008-4042
Year: 1998
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Interdeterminancy of basin and surface properties of an open system
Article Abstract:
Interdeterminancy of surface and basin properties in an open system reflects a significant physical consequence of the Heisenberg equation of motion governing expectation value of an observable for a proper open system. Such a system has a basin bounded by a surface of zero flux in the gradient vector field of the electron density. The surface of the system is dependent on its properties and vice versa. Recent criticisms of the interdependence of the basin and surface properties of a proper open system have been refuted.
Publication Name: Canadian Journal of Chemistry
Subject: Chemistry
ISSN: 0008-4042
Year: 1998
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Cyclic-acyclic equilibrium and selective P-O bond cleavage in 2-hydroxyphenyldiplyenylphosphinate, Ph2P(O)OC6H4OH
Article Abstract:
Equilibrium in the Ph2P(O)OC6H4OH-base system may be shifted by variations in concentration of bases, among them pyridine and 1,4-dioxane, and is affected by trifluoroacetic acid. The equilibrium was studied using 31P and 1H NMR. Information about symmetry of phosphorus-contain intermediates came from the 1H NMR spectrum of the catecholyl ring and the ABCD spin system it has. A mechanism that is related to cyclic-acyclic equilibria and selective P-O bond cleavage has been proposed.
Publication Name: Canadian Journal of Chemistry
Subject: Chemistry
ISSN: 0008-4042
Year: 1998
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