Hydrogen in a Nonstoichiometric YBa2Cu3O6.96 Compound: Study by Raman Spectroscopy

Resumo

Raman spectroscopy has been used to study the interactions between the YBa₂Cu₃O_6.96 compound (123) and hydrogen at 150–200°C and their effects on the structure. It has been found that, when the YBa₂Cu₃O_6.96 compound is subjected to hydrogen intercalation and hydration, the transformation of 123 into tetragonal phase (pseudo-124) takes place. In this case, Raman spectra of the YBa₂Cu₃O_6.96 compound, similarly to those of a compound with absorbed water, exhibit antiferromagnetic fluctuations that are not typical of the compound. After hydrogenation, the 123 compound absorbs water under normal conditions and oxygen at temperatures below 300°C.