Proton NMR in Degraded Powder of YBa2Cu3O7-δ

Abstract
Pulsed NMR of 1H has been applied to characterize aged powders of YBa2Cu3O7-δ and its family. A proton site with an internal field of 150 Oe, which is from antiferromagnetically ordered copper moments, has been observed in antiferromagnetic, tetragonal Yba2Cu3O7-δ. A proton signal inside the superconducting region of orthorhombic YBa2Cu3O7-δ has been observed together with signals from regions of nonmagnetic, nonsuperconducting degraded products for both cases. Overall features are interpreted along with a recently proposed topotactic mechanism of hydration reaction.