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arXiv · 1008.0864

Structural trends from a consistent set of single-crystal data of REFeAsO (RE = La, Ce, Pr, Nd, Sm, Gd, and Tb)

F. Nitsche·A. Jesche·E. Hieckmann·Th. Doert·M. Ruck
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Abstract

A new crystal growth technique for single-crystals of REFeAsO (RE = La, Ce, Pr, Nd, Sm, Gd, and Tb) using NaI/KI as flux is presented. Crystals with a size up to 300 $μ$m were isolated for single-crystal X-ray diffraction measurements. Lattice parameters were determined by LeBail fits of X-ray powder data against LaB6 standard. A consistent set of structural data is obtained and interpreted in a hard-sphere model. Effective radii for the rare-earth metal atoms for REFeAsO are deduced. The relation of the intra- and inter-plane distances of the arsenic atoms is identified as limiter of the phase formation, and its influence on Tc is discussed.

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F. Nitsche, A. Jesche, E. Hieckmann, Th. Doert, M. Ruck. 2010-10-13. Structural trends from a consistent set of single-crystal data of REFeAsO (RE = La, Ce, Pr, Nd, Sm, Gd, and Tb). https://doi.org/10.1103/physrevb.82.134514

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