2134/17363 Jennifer A. Rodgers Jennifer A. Rodgers George B.S. Penny George B.S. Penny Andrea Marcinkova Andrea Marcinkova Jan-Willem G. Bos Jan-Willem G. Bos Dmitry A. Sokolov Dmitry A. Sokolov Anna Kusmartseva Anna Kusmartseva Andrew D. Huxley Andrew D. Huxley J. Paul Attfield J. Paul Attfield Suppression of the superconducting transition of R FeAsO1-x Fx (R=Tb, Dy, and Ho) Loughborough University 2015 untagged Physical Sciences not elsewhere classified 2015-04-24 13:59:27 Journal contribution https://repository.lboro.ac.uk/articles/journal_contribution/Suppression_of_the_superconducting_transition_of_R_FeAsO1-x_Fx_R_Tb_Dy_and_Ho_/9408986 A suppression of superconductivity in the late rare-earth R FeAsO1-x Fx materials is reported. The maximum critical temperature (Tc) decreases from 51 K for R=Tb to 36 K for HoFeAsO0.9 F0.1, which has been synthesized under 10 GPa pressure. This suppression is driven by a decrease in the Fe-As-Fe angle below an optimum value of 110.6°, as the angle decreases linearly with unit-cell volume (V) across the R FeAsO1-x Fx series. A crossover in electronic structure around this optimum geometry is evidenced by a change in sign of the compositional d Tc /dV, from negative values for previously reported large R materials to positive for HoFeAsO0.9 F0.1. © 2009 The American Physical Society.