THERMOGRAVIMETRY AND NEUTRON THERMODIFFRACTOMETRY STUDIES OF THE H-YBa2Cu307 SYSTEM
نویسنده
چکیده
The high T, superconducting oxide YBa&usO, --x reacts with hydrogen gas. Thermogravimetric, X-ray and neutron scattering experiments allow us to propose a two-step type of hydrogen bonding. Firstly, a few hydrogen atoms fill some oxygen vacancies and may favourably modify the electron state, giving rise to a slight increase in the critical temperature. Secondly, after a prolonged heating period, the collapse of the YBa&!usO,_, type framework and of superconductivity were observed, and a new, highly hydrogenated material appeared.
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تاریخ انتشار 2002