ISSN:
1572-8927
Keywords:
Solvent proton NMR
;
field-dependent relaxation
;
inner-sphere and outer-sphere complexes
;
transition metal ions
;
complex stability constants
;
complex reorientation in aqueous solution
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract An NMR method is described and applied, which allows the investigation of the first coordination sphere of certain transition metal ions. It is based on the measurement of the solvent proton nuclear magnetic relaxation times both as a function of magnetic field and of concentration of an admixed diamagnetic salt. This procedure enables an unambiguous separation of dynamic effects from ion-pair formation effects, which both can influence the relaxation times. As an application of this method, the complex formation of Mn2+ and Cu2+ with Br−, I−, ClO 4 − , and SO 4 2− in aqueous solution is studied. Thus the hydration numbersn H2O of these cations as a function of anion concentration are obtained, allowing the detection of weak inner-sphere or outersphere complexes. Also several complex stability constants are derived and are compared with literature data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00645515
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