Variability in Exchange Ion Position in Smectite: Dependence on Interlayer Solvent*

V. Berkheiser and M. M. Mortland
Department of Crop and Soil Sciences, Michigan State University, East Lansing, Michigan 48824, U.S.A.
* Journal Article No. 7259, Michigan Agricultural Experiment Station. Work partially supported by National Science Foundation Grant No. MPS74-18201.

Abstract: Full and reduced charge smectite saturated with Na(I), Ca(II), Cu(II), or tetralkylammonium ions were swollen by a series of solvents of various bulk physical properties. In the full charge smectites, swelling occurred in all solvents regardless of the exchange ion or the initial water content. Charge differences did not usually result in differential swelling of the smectite. Little correlation was found between the degree of swelling and the Gutmann donor numbers, bulk dielectric constants, bulk surface tensions, or dipole moments of the solvents. The intensities of the high field Fe(III) resonance (g = 3.6) in the esr spectra of full charge smectite swollen in various solvents reflected variability in exchange ion positions and depended upon the Gutmann donor number of the solvent. Considerable variety in the stereochemistry of Cu(II)-solvent complexes was revealed by esr spectra of the swollen systems.

Clays and Clay Minerals; November 1975 v. 23; no. 5; p. 404-410; DOI: 10.1346/CCMN.1975.0230514
© 1975, The Clay Minerals Society
Clay Minerals Society (www.clays.org)