DENSITY-FUNCTIONAL CALCULATION OF THE CRYSTAL-FIELD INTERACTION IN RARE-EARTH CUPRATES

Examined is the nature of the crystal field (CF) interaction in rare e arth (RE) cuprates using the ab initio calculations based on the local density approximation to the treatment of one-electron crystal potent ial. To calculate the electronic structure we used the full-potential LAPW method (WIEN95 code). This approach, known to be inadequate for t he 4th and 6th-order CF parameters in RE dioxides, is shown to provide a rather good theoretical prediction for the sign as well as for the magnitude of the 2nd order CF parameters in R2CuO4 and RBa2Cu3O7. (C) 1998 Elsevier Science B.V. All rights reserved.