Proton NMR studies on hydrogen-doped high-Tc superconductor

The chemical and adsorption effects of foreign molecules on the properties of high-temperature superconductors

“…The diffusion of hydrogen ceases following exposure of the ceramic to hydrogen at room temperature for three to four months, and the hydrogen atoms form strong O7H bonds. It was found by 1 H NMR spectroscopy that hydrogen diffusion also occurs in hydrogenated YBa 2 Cu 3 O 77x ceramic at T < 200 K. 127 At temperatures from 130 to 92 K, the hydrogen atoms are mostly localised at the O(4) and O(5) lattice points. The inelastic neutron scattering and diffraction methods afforded the vibration spectra of hydrogen atoms in YBa 2 Cu 3 O 77x ceramic treated with hydrogen at 373 K. 128 Only several percent of the absorbed hydrogen participated in the formation of a solid solution; the H atoms occupy the octahedral positions formed by four Y atoms and two Cu atoms at the Cu(2) positions (Fig.…”

Oxygen Content Dependence of 63Cu(1) NQR and Proton NMR in Hydrogen-Doped Antiferromagnetic YBa2Cu3O6+xHy

“…As Cu(l) atoms in the oxygen-deficient layer have no magnetic moment and the internal fields in this layer arising from the moments in the Cu (2) 0 2 plane are cancelled [1][2][3][4], hydrogen atoms in the present compound are expected to be trapped in some sites near Cu(l) atoms, that is similar to the hydrogen site in YBa 2 Cu 3 0 6 94 H V (y = 0.2 and 0.53) [16,17]. Moreover, it is confirmed that the hydrogen in YBa 2 Cu 3 0 6 94 H V (y = 0.2 and 0.53) exists inside the crystal since the temperature dependence of T x of 'H NMR reflects the superconducting state in the sample [17,18]. Therefore, hydrogen does not exist on the surface but inside the crystal in the case of the new three samples (x = 0.07,0.11, and 0.17) and YBC06.1H.…”