Influence of electronic correlations on the ground-state properties of cerium dioxide

The electron-correlation effects on the ground-state properties of CeO(2) are studied by ab initio quantum-chemical methods. For this purpose the method of increments is applied. It combines Hartree-Fock calculations for periodic systems with correlation calculations requiring only information of the corresponding finite-cluster calculations. Using the coupled-cluster approach for the evaluation of the individual increments, we recover 93% of the experimental cohesive energy. The lattice constant and bulk modulus are found to be in good agreement with experimental values. For comparison also the results obtained with density functional methods are presented.