Pressure enhancement of ion mobilities in liquid silicates from computer simulation studies to 800 kilobars

Charles Angell, P. A. Cheeseman, S. Tamaddon

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

Ion dynamics computer simulation methods show that for many liquid silicates, like silica itself, the component diffusion coefficients show anomalous pressure dependences. This implies that their viscosities have negative pressure dependences. Overall, there is an interesting degree of analogy between the fundamental binary solutions of geochemistry and the aqueous solutions of common experience; however, due to the stronger bonding in silicate systems, the anomalies are much more persistent. Diffusivity maxima occur at pressures of 200 to 300 kilobars and are correlated with a prevalence of fivefold coordination of silicon ions. The relevance of these findings to planetary dynamics and thermophysical modeling problems is briefly considered.

Original languageEnglish (US)
Pages (from-to)883-884
Number of pages2
JournalScience
Volume218
Issue number4575
StatePublished - 1982
Externally publishedYes

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pressure dependence
silicates
computerized simulation
augmentation
geochemistry
liquids
diffusivity
ions
diffusion coefficient
viscosity
anomalies
silicon dioxide
aqueous solutions
silicon

ASJC Scopus subject areas

  • General

Cite this

Pressure enhancement of ion mobilities in liquid silicates from computer simulation studies to 800 kilobars. / Angell, Charles; Cheeseman, P. A.; Tamaddon, S.

In: Science, Vol. 218, No. 4575, 1982, p. 883-884.

Research output: Contribution to journalArticle

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