Layer silicates paramagnetic probes

MCBRIDE Paramagnetic Probes of Layer Silicate Surfaces... 

Spectroscopic techniques such as electron spin resonance (ESR) offer the possibility to "probe" the chemical environment of the interlayer regions. With the ESR technique, an appropriate paramagnetic ion or molecule is allowed to penetrate the interlayer, and chemical information is deduced from the ESR spectrum. Transition metal ions, such as Cu2+, and nitroxide radical cations, such as TEMPAMINE (4-amino-2,2,6,6-tetramethylpiperidine N-oxide) have been used as probes in this manner (6-14). Since ESR is a sensitive and non-destructive method, investigations of small quantities of cations on layer silicate clays at various stages... 

McBride, M. B. (1986). Paramagnetic probes of layer silicate surfaces. In Geochemical Processes at Mineral Surfaces, Davis, J. A, and Hayes, K. F., eds., American Chemical Society Washington, D.C., pp. 362-388. 

---