C. Zobel

Evidence for a low-spin to intermediate-spin state transition in LaCoO 3

We present measurements of the magnetic susceptibility and of the thermal expansion of a LaCoO 3 single crystal. Both quantities show a strongly anomalous temperature dependence. Our data are consistently described in terms of a spin-state transition of the Co 3 + ions with increasing temperature from a low-spin ground state (t 6 2 g e 0 g ) to an intermediate-spin state (t 5 2 g e 1 g ) without (100-500 K) and with (>500 K) orbital degeneracy. We attribute the lack of orbital degeneracy up to 500 K to (probably local) Jahn-Teller distortions of the CoO 6 octahedra. A strong reduction or disappearance of the Jahn-Teller distortions seems to arise from the insulator-to-metal transition around 500 K.

Structure, magnetization, and resistivity of La 1 − x M x CoO 3 ( M = Ca , Sr, and Ba)

We present an investigation of the influence of structural distortions in charge-carrier doped

Evidence for orbital ordering in LaCoO3

{\mathrm{La}}_{1\ensuremath{-}x}{M}_{x}{\mathrm{CoO}}_{3}

Spin-state transition and metal-insulator transition in La 1 − x Eu x Co O 3

by substituting

Thermal conductivity, thermopower, and figure of merit of La1-xSrxCoO3

{\mathrm{La}}^{3+}

Anomalous expansion and phonon damping due to the Co spin-state transition in RCoO3 (R=La, Pr, Nd, and Eu)

with alkaline-earth metals of strongly different ionic sizes, that is,

Magnetic and structural transitions in La 1 − x A x CoO 3 ( A = Ca , Sr, and Ba)

M={\mathrm{Ca}}^{2+},

Experimental quest for orbital waves

{\mathrm{Sr}}^{2+},

Experimental quest for orbital waves: Orbital physics (Communication arising)

and