Water Structure and Dynamics in Smectites: X-ray Diffraction and 2H NMR Spectroscopy of Mg–, Ca–, Sr–, Na–, Cs–, and Pb–Hectorite

• DOI: 10.1021/acs.jpcc.6b03431
• Publication Date: 2016-04-06T18:49:52Z
• Authors: U. Venkateswara R...; Geoffrey M. Bowers; Narasimhan Logana...; Mark Bowden; A. Ozgur Yazaydin; R. James Kirkpatrick
• Keywords: Hectorite

Variable-temperature X-ray diffraction and 2H NMR spectroscopy of the smectite mineral, hectorite, containing interlayer Na+, K+, Cs+, Mg2+, Ca2+, Sr2+, Pb2+ equilibrated at 43% relative humidity (RH) mixed with 2H2O to form a paste provide comprehensive picture structural environments dynamics relationships these properties hydration state, energy polarizability cation, temperature, formation ice-1h in interparticle pores. The variation basal spacing shown by XRD data correlates well behavior, show for first time hectorites that crystallization causes decrease spacing, likely due removal 2H2O. behavior all samples decreasing temperature reflects frequencies motion rotation molecules around their dipoles, reorientation molecules, exchange between sites coordinated not cations.