title: Evidence of a structural phase transition in superconducting SmFeAsO(1-x)F(x) from 19F NMR.
abstract: We report resistivity, magnetization and (19)F NMR results in a polycrystalline sample of SmFeAsO(0.86)F(0.14). The resistivity and magnetization data show a sharp drop at 48 K indicating a superconducting transition. The nuclear spin-lattice rate (1/T(1)) and spin-spin relaxation rate (1/T(2)) clearly show the existence of a structural phase transition near 163 K in the sample, which also undergoes a superconducting transition. This finding creates interest in exploring whether this is unique for Sm based systems or is also present in other rare-earth based 1111 superconductors.
authors.affiliation: ECMP Division, Saha Institute of Nuclear Physics, Kolkata, India.
authors.forename: M
authors.initials: M
authors.lastname: Majumder
authors.forename: K
authors.initials: K
authors.lastname: Ghoshray
authors.forename: C
authors.initials: C
authors.lastname: Mazumdar
authors.forename: A
authors.initials: A
authors.lastname: Poddar
authors.forename: A
authors.initials: A
authors.lastname: Ghoshray
authors.forename: D
authors.initials: D
authors.lastname: Berardan
authors.forename: N
authors.initials: N
authors.lastname: Dragoe
mesh_terms: D001151:Arsenic / Q000737:chemistry*; D004553:Electric Conductivity; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008968:Molecular Conformation; D044367:Phase Transition; D012493:Samarium / Q000737:chemistry*
chemical_list: D005462:Fluorine Radioisotopes; D012493:Samarium; D007501:Iron; D001151:Arsenic