Structure of Complexes in Solution

Structure of Complexes in Solution Derived from X-Ray Diffraction Measurements Georg Johansson... 

M or Complex NnN X/Y Tentative structure of complexes in solution Rate constant/M-1 s 4 Redox potential/mV (SCE) Ref. ... 

STRUCTURES OF COMPLEXES IN SOLUTION DERIVED FROM X-RAY DIFFRACTION MEASUREMENTS... 

EXAFS has the advantage of giving information on the distribution around a specific atomic species, but is limited to the immediate surrounding of an atom and gives no information on longer distances. It also seems to give less precise information, in particular on coordination numbers, and its use for determining structures of complexes in solution has been limited (7). 

Empirical correlation of intensities of absorption bands with the structure of complexes in solutions have been made for lanthanide complexes. It has been recognized that forced electric-dipole transitions of low intensities, in some cases lower in intensity than those of magnetic-dipole transitions, may indicate that the ligand field has point group symmetry with a center of inversion. This criterion has been used in the determination of the ligand field by symmetry of Eu3+ aquo ion [202], The absorption band intensity ratios have been used to show the octahedral structure [49] of lanthanide hexahalide complexes, LnXg. ... 

Complex formation has also been studied in Japan from view-points of chemical equilibria, reaction kinetics and structures of complexes in solution. Works influenced by J. BJerrum, Sillen and Schwarzenbach and others in North Europe formed an important stream in equilibrium studies in solution. Reaction kinetics were investigated on the basis of the absolute reaction rate developed by Eyring and fast reactions were analyzed by the method established by Eigen. Many young Japanese scientists went to Europe, USA and Canada to accept new ideas and to learn new methods of investigation there. 

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