APPLICATION OF THE IMPROVED REGRESSION METHOD TO DERIVE ΔGF0 OF NON-STOICHIOMETRIC CLAY MINERALS AND THEIR CORRELATIONS WITH COMPOSITIONAL PARAMETERS
- DSpace Home
- →
- Геология России
- →
- ELibrary
- →
- View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.
dc.contributor.author | Kudrat M. | |
dc.contributor.author | Varadachari C. | |
dc.contributor.author | Ghosh K. | |
dc.date.accessioned | 2021-01-23T04:01:49Z | |
dc.date.available | 2021-01-23T04:01:49Z | |
dc.date.issued | 2000 | |
dc.identifier | https://elibrary.ru/item.asp?id=255787 | |
dc.identifier.citation | Chemical Geology, 2000, 168, 3, 225-238 | |
dc.identifier.issn | 0009-2541 | |
dc.identifier.uri | https://repository.geologyscience.ru/handle/123456789/23598 | |
dc.description.abstract | A curvilinear regression method earlier developed by us [Varadachari, C., Kudrat, M., Ghosh, K., 1994. Evaluation of standard free energies of formation of clay minerals by an improved regression method. Clays Clay Miner. 42, 298-307] was utilised here for deriving standard free energies of formation (ΔGf0) of a compositionally wide range of illites, smectites, vermiculites and chlorites. The ΔGf0 values ranged from around -1131 to -1321 kcal/mol for illites, -1097 to -1328 kcal/mol for smectites, -1295 to -1351 kcal/mol for vermiculites and -1596 to -1983 kcal/mol for chlorites. Derived ΔGf0 data were compared with available ΔGf0 data for compositionally similar minerals. In spite of some differences in their compositions, the values were within a close range (about +/-0.3-0.5%). Statistical analysis of the relationships between ΔGf0 and ionic contents for the different clay groups were done. ΔGf0 of illites showed strong correlations with Fe3+ and (VI) Al3+ (octahedral Al); the values became more negative with increasing (VI) Al3+ and less negative with increasing Fe3+ in the structure. A regression equation involving Si4+, (IV) Al3+ (tetrahedral Al), (VI) Al3+, Fe3+, Fe2+, Mg2+ and K+ gave a high regression coefficient, r2=0.998. ΔGf0 of smectites were markedly influenced by the Fe3+ content (higher Fe3+ contents lowered - ΔGf0) and that of chlorites by the Fe2+ and Mg2+ contents (higher Fe2+ lowered - ΔGf0 and higher Mg2+ increased it); vermiculites did not show strong influence of any of the structural ions on the ΔGf0. | |
dc.subject | ILLITE | |
dc.subject | SMECTITE | |
dc.subject | VERMICULITE | |
dc.subject | CHLORITE | |
dc.subject | FREE ENERGY | |
dc.subject | COMPUTATION | |
dc.title | APPLICATION OF THE IMPROVED REGRESSION METHOD TO DERIVE ΔGF0 OF NON-STOICHIOMETRIC CLAY MINERALS AND THEIR CORRELATIONS WITH COMPOSITIONAL PARAMETERS | |
dc.type | Статья |
Files in this item
Files | Size | Format | View |
---|---|---|---|
There are no files associated with this item. |
This item appears in the following Collection(s)
-
ELibrary
Метаданные публикаций с сайта https://www.elibrary.ru