Report of the Double-Molybdate Phase Cs2Ba(MoO4)2 with a Palmierite Structure and Its Thermodynamic Characterization
| Autor: | Eric Colineau, Maikel Rutten, Anna Smith, Lambert van Eijck, Jean Christophe Griveau, Nathan de Zoete |
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| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: | |
| Zdroj: | Inorganic Chemistry: including bioinorganic chemistry, 59(18) Inorganic Chemistry |
| ISSN: | 0020-1669 |
| Popis: | The existence of a novel double-molybdate phase with a palmierite-type structure, Cs2Ba(MoO4)2, is revealed in this work, and its structural properties at room temperature have been characterized in detail using X-ray and neutron diffraction measurements. In addition, its thermal stability and thermal expansion are investigated in the temperature range 298–673 K using high-temperature X-ray diffraction, leading to the volumetric thermal expansion coefficient αV ≈ 43.0 × 10–6 K–1. The compound’s standard enthalpy of formation at 298.15 K has been obtained using solution calorimetry, which yielded ΔfHm°(Cs2Ba(MoO4)2, cr, 298.15 K) = −3066.6 ± 3.1 kJ· mol–1, and its standard entropy at 298.15 K has been derived from low-temperature (2.1–294.3 K) thermal-relaxation calorimetry as Sm°(Cs2Ba(MoO4)2, cr, 298.15 K) = 381.2 ± 11.8 J K–1 mol–1. The existence of Cs2Ba(MoO4)2 with a palmierite structure is reported for the first time. The structure has been characterized by X-ray and neutron diffraction, and the thermal expansion has been measured by high-temperature XRD. Moreover, key thermodynamic properties (standard enthalpy of formation and standard entropy) have been derived from solution calorimetry and low-temperature thermal relaxation calorimetry. |
| Databáze: | OpenAIRE |
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