Antiferromagnetism and Oxygen Deficiency in Single Crystal La sub 2 CuO sub (4-delta).
01 January 1987
Two single crystals of undoped La sub 2 CuO sub 4 have been studied by neutron diffraction in the temperature range between 5K and 300K. In one crystal oxygen vacancies are created by heat treatment and the magnetic properties are found to depend strongly on this treatment. The untreated La sub 2 CuO sub 4 crystal is found to order antiferromagnetically at T sub N ~= 50K and the ordered moment is nu = 0.17 +- 0.05 mu B per Cu atom, while the heat treated crystal orders at T sub N ~= 150K with the moment mu = 0.23 +- 0.05 mu B per Cu atom. The magnetic structure in the ordered phase is the same for the two crystals and is in agreement with previously reported powder results.