Nature of the electronic band gap in lanthanide oxides
Nature of the electronic band gap in lanthanide oxides
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DOI：
10.1103/physrevb.87.125116
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发表时间：
2013-03-13
影响因子：
3.7
通讯作者：
Robertson, John
中科院分区：
文献类型：
--
作者：
Gillen, Roland;Clark, Stewart J.;Robertson, John
技术上重要的镧系/稀土倍半氧化物(Ln(2)O(3), Ln = La，…使用混合密度泛函HSE03， HSE06和筛选交换（sX-LDA）计算了CeO2和Lu。我们发现这些密度泛函方法描述了强相关的lnf电子以及最近的G(0)W(0)@LDA+U结果，通常可以得到正确的带隙和贯穿Ln周期的趋势。对于HSE， o2p态和镧系元素5d态之间的能带间隙几乎与镧系元素无关，而最小能带间隙随着填充或空的ln4f态进入该能带间隙而变化。sX-LDA预测了高能量下未占据的4f能级，这与Sm2O3、Eu2O3和Yb2O3的实验结果吻合得更好。
Accurate electronic structures of the technologically important lanthanide/rare-earth sesquioxides (Ln(2)O(3), with Ln = La,..., Lu) and CeO2 have been calculated using hybrid density functionals HSE03, HSE06, and screened exchange (sX-LDA). We find that these density functional methods describe the strongly correlated Ln f electrons as well as the recent G(0)W(0)@LDA+U results, generally yielding the correct band gaps and trends across the Ln period. For HSE, the band gap between O 2p states and lanthanide 5d states is nearly independent of the lanthanide, while the minimum gap varies as filled or empty Ln 4f states come into this gap. sX-LDA predicts the unoccupied 4f levels at higher energies, which leads to a better agreement with experiments for Sm2O3, Eu2O3, and Yb2O3.