TY - JOUR
T1 - A temperature-dependent structural investigation of electrical transitions in A3conb2o9 perovskites (A=Ca2+, Sr2+, Ba2+)
AU - Ting, Valeska
AU - Liu, Y
AU - Withers, R
PY - 2006
Y1 - 2006
N2 - Upon heating, the 1:2 triple perovskites A3CoNb2O9 (A=Ca, Sr or Ba) each undergo well-defined insulator to conductor phase transitions at ∼8, ∼126 and ∼325 °C,
respectively. As the trend in the transition temperatures for these
materials does not correlate with the size of the reported band gaps,
neutron powder diffraction has been used to investigate if this change
in electrical behaviour of the materials was due to a structural phase
change. It was found that in the regions of the suspected phase
transitions there were only slight perturbations of the structures,
namely thermal expansion of the lattices and an apparent muting of the
amplitude of the octahedral rotations in the A=Ca and Sr compound at higher temperatures.
AB - Upon heating, the 1:2 triple perovskites A3CoNb2O9 (A=Ca, Sr or Ba) each undergo well-defined insulator to conductor phase transitions at ∼8, ∼126 and ∼325 °C,
respectively. As the trend in the transition temperatures for these
materials does not correlate with the size of the reported band gaps,
neutron powder diffraction has been used to investigate if this change
in electrical behaviour of the materials was due to a structural phase
change. It was found that in the regions of the suspected phase
transitions there were only slight perturbations of the structures,
namely thermal expansion of the lattices and an apparent muting of the
amplitude of the octahedral rotations in the A=Ca and Sr compound at higher temperatures.
U2 - 10.1016/j.physb.2006.05.358
DO - 10.1016/j.physb.2006.05.358
M3 - Article (Academic Journal)
SN - 0921-4526
VL - 385-386
SP - 558
EP - 560
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
IS - 1
ER -