Journal of Inorganic and General Chemistry
SHORT COMMUNICATION
Zeitschrift für anorganische und allgemeine Chemie
argon atmosphere (Ar 99.999%, 100 mL·min–1, dried, and subjected
to oxygen post-purification with a Big Oxygen Trap, Trigon Technol-
ogies), using an STA 449 C (Netzsch).
The individual samples were measured under comparable conditions
(sample masses: 25–28 mg, rate of heating and cooling: 2 K·min–1,
crucible: corundum with perforated lid, thermocouple: PtRh/Pt). The
temperature ranges applied were 25 to 700 °C for KO2, 25 to 800 °C
for RbO2 and CsO2 for the measurements in an argon atmosphere, and
25 to 450 °C for KO2 and RbO2, 25 to 600 °C for CsO2 for the vacuum
measurements, respectively. The detected mass changes depending on
temperature were subjected to buoyancy correction in accordance with
the measurement conditions.
Laboratory X-ray Powder Diffraction was performed with an Image
Plate Guinierkamera HUBER G670 (Cu-Kα1, λ = 0.154056 nm) at
room temperature in the 2θ range 5 to 90°.
Keywords: Alkali metal oxides; Thermal decomposition;
Synthesis of alkali metal sesquioxides; Alkali metals
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Figure 2. Le Bail fits of the X-ray powder diffractograms of as ob-
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