In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca3Mn2O7 under pressures up to 35 GPa have been Performed by using diamond anvil cell with synchrotron radiat...In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca3Mn2O7 under pressures up to 35 GPa have been Performed by using diamond anvil cell with synchrotron radiation.The results show that the structure of layered perovskite-like manganate Ca3Mn2O7 is unstable under pressure due to the easy compression of NaCl-type blocks.The structure of Ca3Mn2O7 underwent two phase transitions under pressures in the range of 0-35GPa.One was at about 1.3GPa with the crystal structure changing from tetragonalt go orthorhombic.The other was at about 9.5GPa with the crystal structure changing form orthorhombic back to another tetragonal.展开更多
The perovskite-like structure compound Ca0.85- CuO2 has interesting structural properties: it has infinite one-dimensional edge-sharing copper-oxygen chains as well as partial occupancy of the Ca sites resulting in an...The perovskite-like structure compound Ca0.85- CuO2 has interesting structural properties: it has infinite one-dimensional edge-sharing copper-oxygen chains as well as partial occupancy of the Ca sites resulting in an incom-mensurate superstructure. In situ high-pressure energy dis-persive X-ray diffraction measurements on polycrystalline powder Ca0.85CuO2 have been performed by using diamond anvil cell (DAC) instrument with synchrotron radiation. The results for the first time show that edge-sharing copper oxide Ca0.85CuO2 undergoes a structural transition at 14.5 GPa, and furthermore the structural transition is reversible.展开更多
文摘In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca3Mn2O7 under pressures up to 35 GPa have been Performed by using diamond anvil cell with synchrotron radiation.The results show that the structure of layered perovskite-like manganate Ca3Mn2O7 is unstable under pressure due to the easy compression of NaCl-type blocks.The structure of Ca3Mn2O7 underwent two phase transitions under pressures in the range of 0-35GPa.One was at about 1.3GPa with the crystal structure changing from tetragonalt go orthorhombic.The other was at about 9.5GPa with the crystal structure changing form orthorhombic back to another tetragonal.
文摘The perovskite-like structure compound Ca0.85- CuO2 has interesting structural properties: it has infinite one-dimensional edge-sharing copper-oxygen chains as well as partial occupancy of the Ca sites resulting in an incom-mensurate superstructure. In situ high-pressure energy dis-persive X-ray diffraction measurements on polycrystalline powder Ca0.85CuO2 have been performed by using diamond anvil cell (DAC) instrument with synchrotron radiation. The results for the first time show that edge-sharing copper oxide Ca0.85CuO2 undergoes a structural transition at 14.5 GPa, and furthermore the structural transition is reversible.