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Heat capacities and thermodynamic properties of annite (aluminous iron biotite)

January 1, 1990

The heat capacities have been measured between 7 and 650 K by quasi-adiabatic calorimetry and differential scanning calorimetry. At 298.15 K and 1 bar, the calorimetric entropy for our sample is 354.9??0.7 J/(mol.K). A minimum configurational entropy of 18.7 J/(mol.K) for full disorder of Al/Si in the tetrahedral sites should be added to the calorimetric entropy for third-law calculations. The heat capacity equation [Cp in units of J/mol.K)] Cp0 = 583.586 + 0.075246T - 3420.60T-0.5 - (4.4551 ?? 106)T-2 fits the experimental and estimated heat capacities for our sample (valid range 250 to 1000 K) with an average deviation of 0.37%. -from Authors

Publication Year 1990
Title Heat capacities and thermodynamic properties of annite (aluminous iron biotite)
Authors B. S. Hemingway, R. A. Robie
Publication Type Article
Publication Subtype Journal Article
Series Title American Mineralogist
Index ID 70016292
Record Source USGS Publications Warehouse