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arXiv · 1103.0294

Local structural studies of Ba$_{1-x}$K$_x$Fe$_2$As$_2$ using atomic pair distribution function analysis

B. Joseph·V. Zinth·M. Brunelli·B. Maroni·D. Johrendt·L. Malavasi
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Abstract

Systematic local structural studies of Ba$_{1-x}$K$_x$Fe$_2$As$_2$ system are undertaken at room temperature using atomic pair distribution function (PDF) analysis. The local structure of the Ba$_{1-x}$K$_x$Fe$_2$As$_2$ is found to be well described by the long-range structure extracted from the diffraction experiments, but with anisotropic atomic vibrations of the constituent atoms ($U_{11}$ = $U_{22} \ne U_{33}$). The crystal unit cell parameters, the FeAs$_4$ tetrahedral angle and the pnictogen height above the Fe-plane are seen to show systematic evolution with K doping, underlining the importance of the structural changes, in addition to the charge doping, in determining the properties of Ba$_{1-x}$K$_x$Fe$_2$As$_2$.

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B. Joseph, V. Zinth, M. Brunelli, B. Maroni, D. Johrendt, L. Malavasi. 2011-03-01. Local structural studies of Ba$_{1-x}$K$_x$Fe$_2$As$_2$ using atomic pair distribution function analysis. https://doi.org/10.1088/0953-8984%2F23%2F11%2F112202

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