Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-20T01:39:30.306Z Has data issue: false hasContentIssue false
  • English
  • Français

Computer calculation of water-clay interactions using atomic pair potentials

Published online by Cambridge University Press:  09 July 2018

N. T. Skipper ,
K. Refson  and
J. D. C. McConnell
N. T. Skipper
Affiliation:
Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR
K. Refson
Affiliation:
Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR
J. D. C. McConnell
Affiliation:
Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR
Get access Rights & Permissions [Opens in a new window]

Abstract

Existing data on interatomic potentials have been used to study the interactions between an uncharged clay sheet and a water molecule. Calculations show that most of the clay surface is relatively hydrophobic, with binding energies for a water molecule in the range 1·0–4·5 kcal mol−1. There is, however, a low-energy site for an oriented water molecule above the layer OH group and within the ring of six SiO4 tetrahedra. Using two different models for the interactions, the binding energy in this position is found to be either 13·2 or 21·8 kcal mol−1. The existence of the low-energy site accounts for the formation of the hydrated ‘10 Å’ phase of talc, which is known from high-pressure experiments. Data on the PT stability of this phase can be used to estimate its energy of dehydration. This quantity is shown to be consistent with the value of 21·8 kcal mol−1 for the binding energy of a water molecule and the energy associated with the expansion of the layers from the 9·35 Å phase.

Type
Research Article
Information
Clay Minerals , Volume 24 , Issue 2 , June 1989 , pp. 411 - 425
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alcover, J.F. & Giese, R.F. (1986) Energie de liason des feuillets de talc, pyrophyllite, muscovite et phlogopite. Clay Miner., 21, 159–169.Google Scholar
Berthaut, F. (1952) L' energie electrostatique de reseaux ioniques. J. Phys. Radium, 13, 499–505.Google Scholar
Brindley, G.W. & Brown, G. (1980) Crystal Structures of Clay Minerals and their X-ray Identification. Mineralogical Society, London.CrossRefGoogle Scholar
Busing, W.R. (1970) An interpretation of the structure of alkaline earth chlorides in terms of interionic forces. Trans. Am. Cryst. Assoc., 6, 57–60.Google Scholar
Finney, J.L., Quinn, J.E. & Baum, J.O. (1986) The water dimer potential surface. Water Science Reviews, 1, 93.Google Scholar
Huggins, M.L. (1937) Lattice energies, equilibrium distances, compressibilities and characteristic of alkali halide crystals. J. Chem. Phys., 5, 143–148.CrossRefGoogle Scholar
Marchese, F.T., Mehotra, P.K. & Beveridge, D.L. (1982) Transferable potential functions from quantum mechanical calculations of intermolecular interaction energies. J. Chem. Phys., 86, 2592–2601.CrossRefGoogle Scholar
Matsuoka, O. Clementi, E. & Yoshimine, M. (1976) Cl study of the water dimer potential surface. J. Chem. Phys., 64, 1351–1361.CrossRefGoogle Scholar
Parry, D.E. (1975) The electrostatic potential in the surface region of an ionic crystal. Surface Sci., 49, 433–440.Google Scholar
Price, G.D., Parker, S.C. & Leslie, M. (1987) The lattice dynamics and thermodynamics of the Mg2Si04 polymorphs. Phys. Chem. Miner., 15, 181–190.Google Scholar
Ramdas, S. & Thomas, J.M. (1977) The use of atom-atom potentials in interpreting the behaviour of organic molecular crystals. Chemical Physics of Solids and their Surfaces, 7, 31–48. The Chemical Society, London. Google Scholar
Sauer, J., Morgeneyer, C. & Schroder, K.-P. (1984) Transferable analytical potential based on nonempirical quantum chemical calculations (QPEM) for water-silica interactions. 7. Phys. chem., 88, 6375–6383.Google Scholar
Wojcik, M. (1985) MD Simulation of MCY water using LCAP. IBM Tech. Rep. KGN-28.Google Scholar
Yamamoto, K. & Akimoto, S.-L. (1977) The system Mg0-Si03-H20 at high pressure and temperatures— stability field for hydroxyl-chrondrodite, hydroxyl-clinohumite and 10 A phase. Am. J. Sci., 277, 288–312.CrossRefGoogle Scholar