论文信息 - Physical pressure effect on the charge-ordering transition ofBaSmFe2O5.0

Physical pressure effect on the charge-ordering transition ofBaSmFe2O5.0

Pressure effects on the charge-ordering (CO) transition have been investigated in BaSmFe 2 O 5 . 0 by means of synchrotron-radiation x-ray powder-diffraction measurement together with a specially designed diamond anvil cell. It was found that the critical temperature T C O for the CO transition steeply (-56 K/GPa) decreases as pressure increases, and eventually the CO transition disappears about 2.6 GPa. Search for interrelations between the structural parameters and T C O revealed that orthorhombic distortion s [≡(a-b)/(a+b)], is the dominant structural parameter for the CO transition of BaSmFe 2 O 5 . 0 .

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