Backbone structure group-11 metals

The Raman vibration of the symmetric stretching of the phosphodiester group -5 -CH2-O-PO2-O- appears at 814 cm and is slightly altered on fixation of a metal to the phosphate group.lt has been shown (8) that the intensity of the Raman line at 814 cm is a measure of the conformation in the tRNA backbone.The intensity of the above line undergoes a decrease of about 20% when the Mg " ions are extracted with a chelating agent (EDTA) and suitable dialysis. The backbone structure is... 

Nearly 50 crystal structure determinations of examples of 5 and 6 have now been determined and reveal that the geometry at the five-coordinate metal centres can be anywhere between square-pyramidal and trigonal bipyramidal (CSD search April 2008). For example, in [2,6-(ArN=CMe)2C5H3N]FeCl2 (5 Ar = 2,6-i-Pr2C6H3) a distorted square-pyramidal geometry at the metal is exhibited with the arylimino groups almost perpendicular to the plane of the bis(imino)pyridine backbone (Fig. 5) [5, 6], The overall result is that the metal centre is protected both above and below... 

Many of these systems employ charged polymers or polyelectrolytes that confer on them particular properties due to the existence of electrical charges in the polymer structure. Oyama and Anson [14,15] introduced polyelectrolytes at electrode surfaces by using poly(vinylpiridine), PVP, and poly-(acrylonitrile) to coordinate metal complexes via the pyridines or nitrile groups pending from the polymer backbone. Thomas Meyer s group at North Carolina [16, 17[ also employed poly(vinylpyridine) to coordinate Ru, Os, Re and other transition-metal complexes by generating an open coordination site on the precursor-metal complex. 

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