Ratcliff Laura E, Genovese Luigi, Park Hyowon, Littlewood Peter B, Lopez-Bezanilla Alejandro
Department of Materials, Imperial College London, London SW7 2AZ, United Kingdom.
Univ. Grenoble Alpes, CEA, INAC-SP2M, L_Sim, F-38000, Grenoble, France.
J Phys Condens Matter. 2021 Dec 15;34(9). doi: 10.1088/1361-648X/ac3cf1.
A detailed exploration of the-atomic orbital occupancy space for UOis performed using a first principles approach based on density functional theory (DFT), employing a full hybrid functional within a systematic basis set. Specifically, the PBE0 functional is combined with an occupancy biasing scheme implemented in a wavelet-based algorithm which is adapted to large supercells. The results are compared with previous DFT +calculations reported in the literature, while dynamical mean field theory is also performed to provide a further base for comparison. This work shows that the computational complexity of the energy landscape of a correlated-electron oxide is much richer than has previously been demonstrated. The resulting calculations provide evidence of the existence of multiple previously unexplored metastable electronic states of UO, including those with energies which are lower than previously reported ground states.
使用基于密度泛函理论（DFT）的第一性原理方法，在系统的基组内采用完全杂化泛函，对UO的原子轨道占据空间进行了详细探索。具体而言，将PBE0泛函与基于小波算法实现的占据偏置方案相结合，该算法适用于大型超胞。将结果与文献中报道的先前DFT +计算结果进行比较，同时还进行了动态平均场理论计算以提供进一步的比较基础。这项工作表明，关联电子氧化物能量景观的计算复杂性比以前所证明的要丰富得多。所得计算结果证明了UO存在多个先前未探索的亚稳电子态，包括那些能量低于先前报道的基态的电子态。
