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Materials 286K [email protected]
Class 08. LnNiO3
LaNiO3 and LaCuO3 are some of the few (undoped) metals.
Materials 286K [email protected]
Class 08. LnNiO3
Strong lattice effects in the M–I transition of LnNiO3
Torrance, Lacorre, Nazzal, Ansaldo, Niedermayer, Phys. Rev. B. 45 (1992) 8209–8212.
Materials 286K [email protected]
The transition is nicely tunable with average rare-earth size
Class 08. LnNiO3
Medarde et al., J. Phys. Condensed Matter 9 (1997) 1679.
Materials 286K [email protected]
Obradors et al. Phys. Rev. B 47 (1993) 12353.
Pressure effects --- high pressures are like large A-cations
Class 08. LnNiO3
Materials 286K [email protected]
Medarde, Lacorre, Conder, Fauth, Furrer, Phys. Rev. Lett. 80 (1998) 2397–2400.
Lattice dynamics is important: Strong isotope effect
Class 08. LnNiO3
Materials 286K [email protected]
Class 08. LnNiO3
The room-temperature crystal structures
Medarde et al., J. Phys. Condensed Matter 9 (1997) 1679.
Materials 286K [email protected]
Perovskite structures: Group-subgroup relations
Class 08. LnNiO3
from James Rondinelli, Northwestern.
Materials 286K [email protected]
The complete phase diagram
orthorhombic
monoclinic
Class 08. LnNiO3
from James Rondinelli, Northwestern.
Materials 286K [email protected]
Monoclinic phase
Class 08. LnNiO3
from James Rondinelli, Northwestern.
Materials 286K [email protected]
Decomposing the monoclinic structure into into its irreducible representations:
=
Class 08. LnNiO3
from James Rondinelli, Northwestern.
Materials 286K [email protected] 11
TMI – metal-insulator transition correlates with rotations, breathing & bending of octahedra, while TN – AFM ordering transition correlates with first-order Jahn-Teller type of distortions
Breathing distortion correlates with MIT
Jahn-Teller distortion correlates with magnetism
Balachandran, Rondinelli, Phys. Rev. B 88 (2013) 054101.
Class 08. LnNiO3
Materials 286K [email protected] 12
First-order localized to delocalized transition in LaCoO3
Raccah, Goodenough, Phys. Rev. 155 (1967) 932–943.
Class 08. LnCoO3
Materials 286K [email protected] 13
First-order localized to delocalized transition in LaCoO3
Raccah, Goodenough, Phys. Rev. 155 (1967) 932–943.
Class 08. LnCoO3
Materials 286K [email protected] 14
First-order localized to delocalized transition in LaCoO3
Raccah, Goodenough, Phys. Rev. 155 (1967) 932–943.
Class 08. LnCoO3
Materials 286K [email protected] 15
More subtle structural effects (orbital ordering?):
Maris, Ren, Volotchaev, Lorenz, Palstra, Phys. Rev. B. 67 (2003) 224423(1–5).
Class 08. LnCoO3
Materials 286K [email protected] 16
M–I transition with temperature and hole doping (Sr substitution)
Bhide, Rajoria, Rao, Rama Rao, Jadhao, Phys. Rev. B. 12 (1975) 2832–2843.
Class 08. LnCoO3
Materials 286K [email protected] 17
La0.5Sr0.5CoO3–d prepared under different annealing conditions
Haggerty, Seshadri, J. Phys. Condensed Matter 16 (2004) 6477–6484.
Class 08. LnCoO3
Materials 286K [email protected] 18
Haggerty, Seshadri, J. Phys. Condensed Matter 16 (2004) 6477–6484.
Class 08. LnCoO3
La0.5Sr0.5CoO3–d prepared under different annealing conditions
Materials 286K [email protected] 19
La0.5Sr0.5CoO3 band structure. Majority and minority bands have very different bandwidths.
Haggerty, Seshadri, J. Phys. Condensed Matter 16 (2004) 6477–6484.
Class 08. LnCoO3
