TY - JOUR
T1 - Oxygen isotope effect on metal-insulator transition in layered cobaltites RBaCo2O5.5 (R = Pr, Dy, Ho and Y)
AU - Conder, K.
AU - Pomjakushina, E.
AU - Pomjakushin, V.
AU - Stingaciu, M.
AU - Streule, S.
AU - Podlesnyak, A.
PY - 2005/9/21
Y1 - 2005/9/21
N2 - Both differential scanning calorimetry and powder neutron diffraction have been applied to investigate an oxygen isotope effect on the metal-insulator (MI) transition in layered cobaltites RBaCo2O5.5 (R ≤ Pr, Dy, Ho and Y). For all the compounds it was found that 18O substitution increases the transition temperature TMI by about 2 K. A small negative isotope-effect coefficient α0∼-0.06 indicates that a delocalization of the pd σ holes in the Co3+ high spin state (rather than a spin-state transition) can be responsible for the MI transition, in agreement with density-functional calculations (Wu 2003 J. Phys.: Condens. Matter 15 503).
AB - Both differential scanning calorimetry and powder neutron diffraction have been applied to investigate an oxygen isotope effect on the metal-insulator (MI) transition in layered cobaltites RBaCo2O5.5 (R ≤ Pr, Dy, Ho and Y). For all the compounds it was found that 18O substitution increases the transition temperature TMI by about 2 K. A small negative isotope-effect coefficient α0∼-0.06 indicates that a delocalization of the pd σ holes in the Co3+ high spin state (rather than a spin-state transition) can be responsible for the MI transition, in agreement with density-functional calculations (Wu 2003 J. Phys.: Condens. Matter 15 503).
UR - http://www.scopus.com/inward/record.url?scp=24644497692&partnerID=8YFLogxK
U2 - 10.1088/0953-8984/17/37/016
DO - 10.1088/0953-8984/17/37/016
M3 - Article
AN - SCOPUS:24644497692
SN - 0953-8984
VL - 17
SP - 5813
EP - 5820
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
IS - 37
ER -