Measurement of charge transfer in YBa2Cu3O7 using a novel electron diffraction method

摘要

We present a novel experimental approach, based on electron diffraction, of determining the amplitudes and phases of Bragg reflections at low angles. This technique was used to measure charge transfer in YBa2Cu3O7. The determined value of the structure factor of the (001) reflection, which is very sensitive to the distribution of valence electron in the crystal unit cell, corresponds in the purely ionic model to 76 +/- 8% of the electron holes being located in the CuO2 planes of fully oxygenated samples.