Direct observation of the influence of the As-Fe-As angle on the Tc of superconducting SmFeAsO1-xFx

G. GARBARINO; R. WEHT; A. SOW; A. SULPICE; P. TOULEMONDE; M. ÁLVAREZ-MURGA; P. STROBEL; P. BOUVIER; M. MEZOUAR; M. NÚÑEZ-REGUEIRO

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Año: 2011 vol. 84 p. 45101 - 45105

1098-0121

The electrical resistivity, crystalline structure, and electronic properties calculated from the experimentally measured atomic positions of the compound SmFeAsO_0.81 F_0.19 have been studied up to pressures up to 20 GPa. The correlation between the pressure dependence of the superconducting transition temperature (Tc ) and crystallographic parameters on the same sample shows clearly that a regular FeAs4 tetrahedron maximizes Tc through optimization of carrier transfer to the FeAs planes as indicated by the evolution of the electronic band structures.