论文标题
通过OCC-RI-K更快地交换固体：应用于合并范围分离的混合功能，用于与基集限制附近的具有伪电位的简单固体
Faster Exact Exchange for Solids via occ-RI-K: Application to Combinatorially Optimized Range-Separated Hybrid Functionals for Simple Solids with Pseudopotentials Near the Basis Set Limit
论文作者
论文摘要
在这项工作中，我们开发并展示了OCC-RI-K算法，以计算在基集限制附近固体的密度功能计算中的确切交换贡献。在高斯Planewave（GPW）密度拟合中，与常规的GPW算法相比，我们的算法达到了1-2个数量级的速度。由于我们的算法非常适合具有较大基集的模拟，因此我们将其应用于具有伪能力的12个混合密度函数，并以较大的未定基础设置为基础，以评估其在基集限制附近的25个简单固体的频带间隙上的性能。在这项工作中执行的最大计算涉及利用6x6x6 k-mesh的单位电池中的16个电子和350个基本函数。 With 20-27\% exact exchange, global hybrid functionals (B3LYP, PBE0, revPBE0, B97-3, SCAN0) perform similarly with a root-mean-square-deviation (RMSD) of 0.61-0.77 eV while other global hybrid functionals such as M06-2X (2.02 eV) and MN15 (1.05 eV) show higher RMSD due to their increased fraction of exact exchange. HSE是短距离混合功能，达到了类似的RMSD（0.76 eV），但由于完全缺乏远距离交换，因此对频带隙的低估显着低估。我们发现，两个通过组合优化的范围分离的混合功能，$ω$ b97x-rv（3.94 eV）和$ω$ b97亿-RV（3.40 eV），以及其他两个分离的混合功能，cam-b3lyp（2.41 ev）和cam-qtp01 ev（4.16 ev），大量交换了较高的速度，因为他们的频率很高。鉴于$ω$ B97X-RV和$ω$ b97亿-RV的故障，我们尚未找到一个密度功能，可为分子和固体提供一致的性能。我们的算法开发和密度功能评估将成为开发更准确的混合功能并将其应用于实际应用的垫脚石。
In this work, we developed and showcased the occ-RI-K algorithm to compute the exact exchange contribution in density functional calculations of solids near the basis set limit. Within the gaussian planewave (GPW) density fitting, our algorithm achieves a 1-2 orders of magnitude speedup compared to conventional GPW algorithms. Since our algorithm is well-suited for simulations with large basis sets, we applied it to 12 hybrid density functionals with pseudopotentials and a large uncontracted basis set to assess their performance on band gaps of 25 simple solids near the basis set limit. The largest calculation performed in this work involves 16 electrons and 350 basis functions in the unit cell utilizing a 6x6x6 k-mesh. With 20-27\% exact exchange, global hybrid functionals (B3LYP, PBE0, revPBE0, B97-3, SCAN0) perform similarly with a root-mean-square-deviation (RMSD) of 0.61-0.77 eV while other global hybrid functionals such as M06-2X (2.02 eV) and MN15 (1.05 eV) show higher RMSD due to their increased fraction of exact exchange. A short-range hybrid functional, HSE achieves a similar RMSD (0.76 eV) but shows a noticeable underestimation of band gaps due to the complete lack of long-range exchange. We found that two combinatorially optimized range-separated hybrid functionals, $ω$B97X-rV (3.94 eV) and $ω$B97M-rV (3.40 eV), and the two other range separated hybrid functionals, CAM-B3LYP (2.41 eV) and CAM-QTP01 (4.16 eV), significantly overestimate the band gap because of their high fraction of long-range exact exchange. Given the failure of $ω$B97X-rV and $ω$B97M-rV, we have yet to find a density functional that offers consistent performance for both molecules and solids. Our algorithm development and density functional assessment will serve as a stepping stone towards developing more accurate hybrid functionals and applying them to practical applications.
