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LaCu3Cr4O12 (I) and YCu3Cr4O12 (II) are prepared by high pressure reactions of Ln2O3 (Ln: La, Y), CuO, Cr2O3, and CrO2 in the molar ratio 1:6:0.5:7 (Au capsules, 9 GPa, 900 °C, 30 min).

The room temperature structures and temperature induced structural phase transitions of the title compounds are determined by X-ray, synchrotron radiation, and neutron powder diffraction.

The catalyst can be recycled and reused in four cycles without any significant loss of catalytic activity.

This feature article provides, for the first time, an overview of the research that guided the way from fundamental studies of the thermo-responsive phase separation of aqueous polymer solutions to polymeric sensor systems. The incorporation of solvatochromic dyes into thermoresponsive polymers as well as the concepts of polymeric sensors are presented and discussed in detail.

Sr2CrSbO6 was synthesized by the conventional solid-state reaction process. X-ray powder diffraction (XRPD) and neutron powder diffraction (NPD) has been used to reinvestigate the structure at room temperature and to study the phase transitions at high- and low-temperature. Rietveld analysis revealed that Sr2CrSbO6 crystallizes at room temperature in a monoclinic system having a space group I2/m, with a=5.5574(1) A; b=5.5782(1) A; c=7.8506(2) A and β=90.06(2), no P21/n space group as was previously reported. The high-temperature study (300–870 K) has shown that the compound presents the following temperature induced phase-transition sequence: I2/m–I4/m–Fm-3m. The low-temperature study (100–300 K) demonstrated that the room-temperature I2/m monoclinic symmetry seems to be stable down to 100 K.