ON THE MOTION OF LITHIUM IN YBA2CU3O7 LITHIATED MATERIALS

Experiments on the chemical lithiation of Ba2YCu3O7 and related materi als have been performed previously by the authors [1-4]. One of the ma in results of that work is the room temperature formation of ''124'' f rom ''123''. Here a simple ionic model is used to give an estimate of the activation energy for lithium motion which is in good agreement wi th experimental values obtained from conductivity measurements. Lithiu m diffusion seems to be favoured in the ''124'' compared with ''123''. This result is discussed on the basis of the structure of these phase s.