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Síntesis, estructura cristalina y propiedades magnéticas del nuevo manganato unidimensional Cs3Mn2O4
Jürgen Nuss1, Maria A Señaris-Rodriguez, Prasad L V K Dasari
1Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
Journal of the American Chemical Society
|June 27, 2012
Resumen
Un nuevo compuesto ternario de manganeso, Cs(3) Mn(2) O(4), exhibe un ordenamiento único de carga en 1D de los iones Mn(2+) y Mn(3+). Este material muestra complejos fenómenos de ordenamiento magnético por debajo de 12 K, impulsados por cadenas antiferromagnéticas acopladas.
Área de la Ciencia:
- Química del estado sólido.
- Ciencia de los materiales Ciencia de los materiales.
- El magnetismo es el magnetismo.
Sus antecedentes:
- Los compuestos ternales de manganeso con valencia mixta son raros.
- Comprender el orden de carga en los óxidos de metales en transición es crucial para las nuevas propiedades electrónicas.
Objetivo del estudio:
- Sintetice y caracterice un nuevo ternario de manganeso (II/III) compuesto de valor mixto.
- Investigar la estructura cristalina, el ordenamiento de la carga y las propiedades magnéticas de Cs(3)Mn(2)O(4).
Principales métodos:
- Ruta de síntesis de azido y nitrato.
- Difracción de rayos X en polvo y cristal único.
- Mediciones de la susceptibilidad magnética.
- Cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- Cs(3)Mn(2)O(4) fue sintetizado y su estructura cristalina determinada (P2(1)/c).
- La estructura se caracteriza por 1D MnO (((2) ((1.5-) cadenas con un completo orden de carga 1:1 de Mn (((2+) y Mn (((3+).
- El acoplamiento antiferromagnético dentro de las cadenas conduce a cadenas ferrimagnéticas, con ordenamiento 3D por debajo de ~12 K, exhibiendo fenómenos dependientes del campo.
Conclusiones:
- Cs(3)Mn(2)O(4) es el primer A(x)MnO(2) intrínsecamente dopado que muestra un orden de carga completo.
- El compuesto exhibe un comportamiento magnético complejo que surge de los cambios de acoplamiento entre cadenas.
- Los cálculos de DFT apoyan el ordenamiento antiferromagnético como el estado fundamental.
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