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arXiv · 1006.2147

Uniform chemical pressure effect in solid solutions Ba(1-x)Sr(x)Fe2As2 and Sr(1-x)Ca(x)Fe2As2

Shanta R. Saha·Kevin Kirshenbaum·Nicholas P. Butch·Peter Y. Zavalij·Johnpierre Paglione
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Abstract

The effect of alkaline earth substitution on structural parameters was studied in high-quality single crystals of Ba(1-x)Sr(x)Fe2As2 and Sr(1-x)Ca(x)Fe2As2 grown by the self-flux method. The results of single-crystal and powder x-ray diffraction measurements suggest a continuous monotonic decrease of both a- and c-axis lattice parameters, the c/a tetragonal ratio, and the unit cell volume with decreasing alkaline earth atomic radius as expected by Vegard's law. As a result, the system experiences a continuously increasing chemical pressure effect in traversing the phase diagram from x=0 in Ba(1-x)Sr(x)Fe2As2 to x=1 in Sr(1-x)Ca(x)Fe2As2.

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Shanta R. Saha, Kevin Kirshenbaum, Nicholas P. Butch, Peter Y. Zavalij, Johnpierre Paglione. 2010-06-10. Uniform chemical pressure effect in solid solutions Ba(1-x)Sr(x)Fe2As2 and Sr(1-x)Ca(x)Fe2As2. https://doi.org/10.1088/1742-6596%2F273%2F1%2F012104

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