Perovskite-type materials containing Bi
3+ cations at A sites are interesting from the viewpoints of applications and fundamental science as the lone pair of Bi
3+ cations often stabilizes polar, ferroelectric structures. This can be illustrated by a lot of discoveries of different
[...] Read more. Perovskite-type materials containing Bi
3+ cations at A sites are interesting from the viewpoints of applications and fundamental science as the lone pair of Bi
3+ cations often stabilizes polar, ferroelectric structures. This can be illustrated by a lot of discoveries of different new functionalities in bulk and thin films of BiFeO
3 and its derivatives. In this work, we investigated solid solutions of BiCr
1−xFe
xO
3 with 0.1 ≤
x ≤ 0.4 prepared by a high-pressure (HP) method and post-synthesis annealing at ambient pressure (AP). HP-BiCr
1−xFe
xO
3 modifications with 0.1 ≤
x ≤ 0.3 were mixtures of two phases with space groups
C2/
c and
Pbam, and the amount of the
C2/
c phase decreased with increasing
x. The amount of the
C2/
c phase was also significantly decreased in AP-BiCr
1−xFe
xO
3 modifications, and the
C2/
c phase almost disappeared in AP-BiCr
1−xFe
xO
3 with 0.2 ≤
x ≤ 0.3. Fundamental, strong reflections of HP-BiCr
1−xFe
xO
3 and AP-BiCr
1−xFe
xO
3 were almost unchanged; on the other hand, weak superstructure reflections were different and showed clear signs of strong anisotropic broadening and incommensurate positions. These structural features prevented us from determining their room-temperature structures. On the other hand, HP-BiCr
1−xFe
xO
3 and AP-BiCr
1−xFe
xO
3 showed high-temperature structural phase transitions to the GdFeO
3-type
Pnma modification at
Tsrt = 450 K (
x = 0.1),
Tsrt = 480 K (
x = 0.2),
Tsrt = 510 K (
x = 0.3), and
Tsrt = 546 K (
x = 0.4). Crystal structures of the GdFeO
3-type
Pnma modifications of all the samples were investigated by synchrotron powder X-ray diffraction. Magnetic properties of HP-BiCr
1−xFe
xO
3 and AP-BiCr
1−xFe
xO
3 were quite close to each other (HP vs. AP), and the
x = 0.2 samples demonstrated negative magnetization phenomena without signs of the exchange bias effect.
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