Uni- and Bivalent Ions

The formation of a ternary complex between proline (HA) and [Cu(bpy)] proceeds through two paths shown in equations (32) and (33), where log ki = 9.25, 

The substitution of tris(4,7-dihydroxyl-l,10-phenanthroline)iron(II), [Fe(ohp)3], by CN to form [Fe(ohp)2(CN)2] has been examined by SF spectrophotometry in a study of the oxidation of [Fe(ohp)3] by H2O2 (no charges are shown as under the basic conditions of the study oph is probably doubly deproton-ated, but the precise charges of the complexes have not been definitely established ). At pH 13 the substitution rate is found to be independent of [CN ] and characterized by k 295 K) = 8.63 x 10 s in aqueous solution at / = 0.11 mol dm (NaCl), consistent with the rate-determining step being the dissociation of ohp. It is deduced from this that the dissociation of ohp is the rate-limiting step in the inner-sphere oxidation of [Fe(ohp)3] by H2O2. 

A newly designed, high-resolution rapid-scan-stopped-flow spectrophotometer has been used to study the sequential aquation reactions shown in equation (34), where ki = 86.6 s k2 = 5.2 s and k = 0.145 s at 298.2 K in 

Axial substitutions have also been studied in the square-pyramidal (acido)(rac-5,5,7,12,12,14-hexamethyl-l,4,8,ll-tetraazacyclotetradecane)copper(II) species in aqueous solution by SF spectrophotometry. Thus for reaction (38) the 

Two SF spectrophotometric studies of the decomplexation of tetraaza macrocyclic complexes have been reported. In the first the decomplexation of N,N N ,N -tetrakis(2-hydroxyethyl)-1,4,8,11 -tetraazacyclotetradecane-copper(II) (CuL ) is characterized by the rate law (39), where /ch(298.2 K) = 

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HCckel, however, agree well with experiment when dilute solutions of uni- and bivalent ions are concerned. It would be out of place to repeat the complicated derivations in this monograph and we must limit our discussion to a mere statement of calculations which can be performed with their aid. 

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