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Doping and bond length contributions to Mn K-edge shift in La$_{1-x}$Sr$_x$MnO$_{3}$ and their correlation with electrical transport properties

S. K. Pandey·R. Bindu·Ashwani Kumar·S. Khalid·A. V. Pimpale
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Abstract

The experimental Mn K-edge x-ray absorption spectra of La$_{1-x}$Sr$_x$MnO$_{3}$, $x$ = 0 - 0.7 are compared with the band structure calculations using spin polarized density functional theory. It is explicitly shown that there is a correspondence between the inflection point on the absorption edge and the centre of gravity of the unoccupied Mn 4$p$-band. This correspondence has been used to separate the doping and size contributions to edge shift due to variation in number of electrons in valence band and Mn-O bond lengths, respectively when Sr is doped into LaMnO$_3$. Such separation is helpful to find the localization behaviour of charge carriers and to understand the observed transport properties of these compounds.

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S. K. Pandey, R. Bindu, Ashwani Kumar, S. Khalid, A. V. Pimpale. 2007-09-03. Doping and bond length contributions to Mn K-edge shift in La$_{1-x}$Sr$_x$MnO$_{3}$ and their correlation with electrical transport properties. https://arxiv.org/abs/cond-mat/0603483

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