Spin-based nomenclature

Extensive analysis of the EPR and redox behavior of this unusual copper protein led to the hypothesis that the protein might contain a Cu(A) site similar to that in cytochrome oxidase (Riester et ai, 1989) and that the unusual seven-line EPR is due to the Cu(A)-type site. An alternative interpretation of this EPR is based on electron spin-echo spectroscopy as well, and that is that the seven-line EPR is due to a half-met Cu—Cu pair and to unusual type I sites (Jin et ai, 1989). Three sets of spin-echo peaks can be attributed to nitrogens on imidazole ligands to a CuA-type site and to another imidazole on the half-met site. The electron spin-echo spectra of cytochrome oxidase are similar, although there is not enough copper in cytochrome oxidase for a half-met site. Conceivably, the property of delocalization of the paramagnetic electron could be effected by the proposed bridging between Cub and heme as (nomenclature summarized by Capaldi, 1990), which are proposed to be 3-4 A apart. 

Also a cluster expansion based on the set of Kekule structures is possible [63], and indeed (in the nomenclature used here) evidently yields the first suggested many-body resonating VB solution scheme (earlier many-body approaches seeking solutions to VB models without much attention to the chemically appealing local spin pairing). 

CONTENTS Introduction to the Series An Editor s Foreword, Albert Padwa, Emory University. Preface, George R. Newkome, University of South Florida. A Review of Dendritic Macromolecules, George R. Newkome and Charles N. Moorefield, University of South Florida. Stiff Dendritic Macromolecules Based on Phenylacetylenes, Zhifu Xu, Benjamin Kyan, and Jeffery S. Moore, The University of Michigan. Preparation and Properties of Monodisperse Aromatic Dendritic Macromolecules, Thomas X. Neenan, Timothy M. Miller, Elizabeth W. Kwock, and Harvey E. Bair, AT T Bell Laboratories. High-Spin Polyarylmethyl Polyradicals, Andrzej Rajca, University of Nebraska. A Systematic Nomenclature for Cascade (Dendritic) Polymers, Gregory R. Baker and James K. Young, University of South Florida. Index. 

Catalytic Chain Transfer. A highly useful variant of chain transfer was discovered in the 1970-1980s in the Soviet Union (216). A number of reviews have been published in recent years (217-221) on this synthetic method which has acquired the nomenclature of either catalytic chain transfer (CCT) or special chain transfer (SCT). The most commonly adopted catalysts are based on low spin cobalt macrocycles, although other metal-containing complexes have also been suggested in the patent and scientific literature. Some typical catalyst structures are shown as 12 and 13. 

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