Weak ferromagnetism and oxygen ordering in La2CuO4+x single crystals

Abstract
The changes produced in the magnetic properties and structure of La2CuO4+x (0< x<0.015) single crystals by doping with oxygen are investigated by differential magnetic susceptibility and x-ray diffraction methods. It is found that the appearance of a weak ferromagnetism in weak fields H<50 Oe is accompanied by a lowering of lattice symmetry as a result of the oxygen ordering.