Search results

Sort By:

Limit search:

Novel Properties of Atomically Arranged Perovskites

100%

Dabrowski B., Kolesnik S., Chmaissem O., Suescun L., Mais J.

Acta Physica Polonica A

2007

vol. 111

issue 1

15-25

Perovskites AMO_{3-δ} attain unique electronic, magnetic, ferroelectric, thermoelectric, mixed-conducting, and other functional properties through selection of the A- and M-site ions, their fractions, ionic sizes and valences, spin states, and orbital orderings, as well as the oxygen content and vacancy ordering. We illustrate here our systematic exploration of the effects of composition, temperature, pressure, and oxygen content on the thermodynamic stability and magnetic properties for La_{1-x-y}Sr_xBa_yMnO_3 manganites. Parameters controlling magnetic transitions are identified through examples of single-valent compounds of RMnO_3 (the Mn-O-Mn bond angles that can be equivalently described in terms of the tolerance factor) and Sr_{1-x}Ca_xMnO_3 (the tolerance factor and disorder described in terms of the variance of A-site ion sizes), and the mixed-valent La_{0.5}Sr_{0.5-y}Ba_yMnO_3 (the tolerance factor, variance of sizes, and the local strains described in terms of the elongated Mn-O bonds). By using an example of kinetically stable, atomically-ordered layered-perovskites we show that improved useful properties, such as the increase in the Curie temperature T_C and enhancement of colossal magneto-resistive effect at room temperature, can be achieved through decreases in structural distortions such as variance of sizes and local strains.

Refine search results

1 Acta Physica Polonica A

1 2007

1 Chmaissem O.

1 Dabrowski B.

1 Kolesnik S.

1 Mais J.

1 Suescun L.

Search results

Novel Properties of Atomically Arranged Perovskites