Chemical interactions and configurational disorder in silicate melts

The Thermodynamics of quasi-chemical and polymeric models are briefly reviewed. It is shown that the two
 classes are mutually consistent, and that opportune conversion of the existing quasi-chemical parameterization
 of binary interactions in MO-SiO2 joins to polymeric models may be...

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Bibliographic Details
Main Author: G. Ottonello
Format: Article
Language:English
Published: Istituto Nazionale di Geofisica e Vulcanologia (INGV) 2005-06-01
Series:Annals of Geophysics
Subjects:
Online Access:http://www.annalsofgeophysics.eu/index.php/annals/article/view/3220
Description
Summary:The Thermodynamics of quasi-chemical and polymeric models are briefly reviewed. It is shown that the two
 classes are mutually consistent, and that opportune conversion of the existing quasi-chemical parameterization
 of binary interactions in MO-SiO2 joins to polymeric models may be afforded without substantial loss of precision.
 It is then shown that polymeric models are extremely useful in deciphering the structural and reactive properties
 of silicate melts and glasses. They not only allow the Lux-Flood character of the dissolved oxides to be
 established, but also discriminate subordinate strain energy contributions to the Gibbs free energy of mixing
 from the dominant chemical interaction terms. This discrimination means that important information on the
 short-, medium- and long-range periodicity of this class of substances can be retrieved from thermodynamic
 analysis. Lastly, it is suggested that an important step forward in deciphering the complex topology of the inhomogeneity
 ranges observed at high SiO2 content can be performed by applying SCMF theory and, particularly,
 Matsen-Schick spectral analysis, hitherto applied only to rubberlike materials.
ISSN:1593-5213
2037-416X