Moureen C. Kemei

Spin-induced symmetry breaking in orbitally ordered NiCr 2O 4 and CuCr 2O 4

At room temperature, the normal oxide spinels NiCr_2O_4 and CuCr_2O_4 are tetragonally distorted and crystallize in the I4_1/amd space group due to cooperative Jahn-Teller ordering driven by the orbital degeneracy of tetrahedral Ni

Crystal structures of spin-Jahn?Teller-ordered MgCr2O4 and?ZnCr2O4

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Antiferromagnetic spin correlations between corner-shared [FeO5]7- and [FeO6]9- units, in the novel iron-based compound: BaYFeO4.

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Evolution of magnetic properties in the normal spinel solid solution Mg1−xCuxCr2O4

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Rapid preparation and magnetodielectric properties of trirutile Cr2WO6

) and Cu

Hydrothermal preparation and magnetic properties of NaFeSi2O6: nanowires vs bulk samples.

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The Pyreno-Triazinyl Radical – Magnetic and Sensor Properties

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Importance of unpaired electrons in organic electronics

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Structural ground states of (A,A′) Cr2 O4 (A = Mg, Zn; A′ = Co, Cu) spinel solid solutions: Spin-Jahn-Teller and Jahn-Teller effects

). Upon cooling, these compounds undergo magnetic ordering transitions; interactions being somewhat frustrated for NiCr_2O_4 but not for CuCr_2O_4. We employ variable-temperature high-resolution synchrotron X-ray powder diffraction to establish that at the magnetic ordering temperatures there are further structural changes, which result in both compounds distorting to an orthorhombic structure consistent with the Fddd space group. NiCr_2O_4 exhibits additional distortion, likely within the same space group, at a yet-lower transition temperature of

Magnetic structure and properties of NaFeSO4F and NaCoSO4F

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