On the ground state of TiO2 as predicted by all electron density functional calculations in relation to experiment

摘要: The energy ordering of rutile and anatase forms TiO2 are reported with several density functionals as obtained using all electron calculations. Careful convergence tests were performed. Results both without structure optimization reported. In each case is found to be more stable than rutile, in contrast the experimental expectation. Upon full relaxation, lattice parameters similar experiment regardless functional used. GGA functionals, which generally regarded reliable LDA for energies, yield a strongly ground state. possibility poor approximation Ti core-electrons pseudopotential methods can excluded source this long standing puzzle. results discussed relation experiment.