Structural studies of the (La, Sr) CrO3 system

Structural Phase Transition of Orthorhombic LaCrO3 Studied by Neutron Powder Diffraction

“…The di!raction data below this temperature were analyzed on the basis of orthorhombic space group Pnma (No. 62, a&5.5 A s , b&7.8 A s , and c&5.5 A s ) (23). On the other hand, the crystal structure of LaCrO at rhombohedral phase has not been reported before.…”

Refinement of crystal structural parameters and charge density using convergent-beam electron diffraction – the rhombohedral phase of LaCrO3

“…The two phases below 2000 K have distorted perovskite structures. It was reported that the space group of the phases above and below the transition temperature of 537 K are rhombohedral R " 3m (Ho È fer & Kock, 1993) and orthorhombic Pbnm (Khattak & Cox, 1977;Berjoan et al, 1980), respectively. Prior to the structure re®nement, we determined using the CBED method that the space groups above and below the transition temperature are respectively R " 3c and Pbnm .…”

Chemical and Thermal Expansion of Calcium-Doped Lanthanum Chromite

“…For the present paper, calculations were limited to the fully oxidized material (heated in air, denoted &&ox'') and the fully reduced material (P(O )"10\ atm, denoted &&red''). This study is also limited to the calciumdoped lanthanum chromites (LCC) because they appear more likely to retain the orthorhombic Pbnm symmetry at higher temperatures (3,14), rather than transforming to rhombohedral symmetry as in the case of strontium doping (15). This simpli"ed the potential derivations by reducing the amount of structural data needed.…”