Superstructures in YBa 2Cu 3O 6+x compounds by neutron and X-ray diffraction

Abstract

In a single crystal of YBa 2Cu 3O 6.35 we determined an oxygen superstructure with a 2√2 aX2√2 acell by neutron diffraction. A 2√2 aX√2 a superstructure of a monodomain has been found by X-ray diffraction. In YBa 2Cu 3O 6.4 of T c=38K, we observed a short range ordered ortho-II structure by neutron single crystal diffraction.