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arXiv · 0909.0839

Electronic structure of the sigma-phase in paramagnetic Fe-V alloys. Experimental and theoretical study

J. Cieslak·J. Tobola·S. M. Dubiel
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Abstract

The electronic structure of $\sigma$-phase Fe$_{100-x}$V$_x$ compounds with 33.3 $\le x \le 60.0$ was calculated from the charge self-consistent Korringa-Kohn-Rostoker method. For the first time, charge densities $\rho_A(0)$ and electric field gradients were determined at Fe nuclei, that occupy five nonequivalent lattice sites. The highest $\rho_A(0)$ values were found on sites A and D, and the lowest one on site B, the difference ranging between 0.162 and 0.174 $\it s$-like electrons per Fe atom for $x = 33.3$ and $x = 60$, respectively. The calculated quantities combined with experimentally determined site occupancies were successfully applied to analyze $^{57}$Fe M\"ossbauer spectra recorded on a series of 8 samples in a paramagnetic state.

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J. Cieslak, J. Tobola, S. M. Dubiel. 2009-09-04. Electronic structure of the sigma-phase in paramagnetic Fe-V alloys. Experimental and theoretical study. https://doi.org/10.1103/physrevb.81.174203

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