Coordination models for

The coordination model for non-aqueous solvent behaviour. R. S. Drago and K. F. Purcell, Prog. Inorg. Chem., 1964, 6, 271-322 (125). 

There has been particular recent interest in zinc nitrate complexes as coordination models for bicarbonate binding in carbonic anhydrase. The mono- or bidentate coordination modes have been studied with tris-pyrazolyl borate complexes and can be rationalized in the context of the enzyme activity.433 Caution in this comparison is introduced by ab initio calculations on these model systems demonstrating both monodentate and bidentate coordination energy minima for nitrate binding to zinc 434... 

Figure 56 Configuration coordinate model for higher-dimensionality polysilanes.360 Reprinted with permission from Watanabe, A. J. Organomet. Chem. 2003, 685, 122-133, 2003 Elsevier.

Figure 11.13. The single configurational coordinate model for Cr5 fluorescence in low-field crystals, r = configurational coordinate.

Fit number Coordination model for the first shell AT Scatterer R(kf CT (A r Fit error ... 

Fig. 7. Configuration coordinate model for the 4/7 and c.t. states (CTS) of Eu3+ in Y2O2S. The dotted curve shows qualitatively the higher position of the CTS in many oxidic hosts. The 4/ states above are indexed by their absorption wavelengths (nm) from After Ref. (70)...

Summary Bulky monodentate ligands affect the structure and reactivity of siliconium ion complexes in several ways they enhance ionization, they promote a methyl halide elimination reaction, and they severely distort complex geometries. The latter effect enabled the assembly of a reaction coordinate model for the Berry pseudorotation, composed of crystal structures with varying NSiN and OSiO bond angles. In a competition between opposing effects of electron withdrawal by CF3 and steric bulk of a cyclohexyl ligand in the same molecule, a nonionic dissociation of the dative N->Si bond was observed. 

Scheme 16. Revised schematic energy versus reaction-coordinate model for progression from an encounter complex to disaccharide taking into account H-bonds from the acceptor (compare Fig.1C, right side). Species Y may be the anionic leaving-group X-, or some other electronegative reaction component. Relative energies are arbitrarily chosen, and may vary from case to case.

Fig. 3.15. Configurational coordinate model for in SrB4<>7. Figs. 3.14 and 3.13 are derived from A. Meijcrink. thesis. University Utrecht, 1990...

Drago, R. S., and Purceil, D. F., The Coordination Model for Non-Aqueous Solvent Behavior 6 271... 

Yi, W., Ozdamar, L. (2007). A dynamic logistics coordination model for evacuation and support in disaster response activities. European Journal of Operational Research, 179, 1177-1193. 

Fig. 6.1 Coordination models for Lewis acid-carbonyl complexes.

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