First-principles study for low-spinLaCoO3with a structurally consistent HubbardU

Abstract

In this paper, we use the local density $\text{approximation}+\text{Hubbard}$ $U$ method to calculate the structural and electronic properties of low-spin ${\text{LaCoO}}_3$. The Hubbard $U$ is obtained by first principles and consistent with each fully optimized atomic structure at different pressures. With structurally consistent $U$, the fully optimized atomic structure agrees with experimental data better than the calculations with fixed or vanishing $U$. A discussion on how the Hubbard $U$ affects the electronic and atomic structures of ${\text{LaCoO}}_3$ is also given.