New thermodynamic data for CoTiO3, NiTiO3 and CoCO3 based on low-temperature calorimetric measurements

作者:Klemme Stephan*; Hermes Wilfried; Eul Mathias; Wijbrans Clazina H; Rohrbach Arno; Poettgen Rainer
来源:Chemistry Central Journal, 2011, 5(1): 54.
DOI:10.1186/1752-153X-5-54

摘要

The low-temperature heat capacities of nickel titanate (NiTiO3), cobalt titanate (CoTiO3), and cobalt carbonate (CoCO3) were measured between 2 and 300 K, and thermochemical functions were derived from the results. Our new data show previously unknown low-temperature lambda-shaped heat capacity anomalies peaking at 37 K for CoTiO3 and 26 K for NiTiO3. From our data we calculate standard molar entropies (298.15 K) for NiTiO3 of 90.9 +/- 0.7 J mol(-1) K-1 and for CoTiO3 of 94.4 +/- 0.8 J mol(-1) K-1. For CoCO3, we find only a small broad heat capacity anomaly, peaking at about 31 K. From our data, we suggest a new standard entropy (298.15 K) for CoCO3 of 88.9 +/- 0.7 J mol(-1) K-1.

  • 出版日期2011-9-19