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晶体有机半导体的基准数据集

Andriy Zhugayevych¹, Wenbo Sun², Tammo van der Heide²

¹Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.

Journal of chemical theory and computation

|November 16, 2023

概括

一个新的晶体有机半导体基准数据集有助于评估用于预测材料性质的计算方法. 结果显示密度函数理论 (DFT) 方法提供精确的几何形状,但单元细胞体积不同.

科学领域:

材料科学材料科学材料科学
计算化学计算化学
固态物理固态物理

背景情况:

准确预测晶体有机半导体特性对于材料设计至关重要.
现有的计算方法需要对实验数据进行严格的基准测试.
需要一个全面的数据集来评估各种理论方法的性能.

研究的目的:

建立一个结晶有机半导体的基准数据集,用于评估计算方法.
测试密度函数理论 (DFT) 函数的准确性,并近似 DFT 方法来预测结构和电子性质.
为了比较不同计算方法在几何学,单元细胞体积和计算成本方面的性能.

主要方法:

编制了67个有机半导体的数据集,并提供了可用的实验性晶体结构.
使用28个晶体的子集对r2SCAN-D3和PBE-D3密度函数进行基准测试,可靠的零温度单元细胞体积估计.
在整个数据集中对r2SCAN-D3进行近似DFT方法 (GFN1-xTB,DFTB3) 的评估,包括分散校正的分析.

主要成果:

r2SCAN-D3在几何学上表现出高精度 (在几百分之内),但系统地低估了大约2%的单元细胞体积.
虽然PBE-D3的速度更快,但它提供了不偏见的体积估计,除了极极性债券,它高估了体积.
大致的DFT方法产生了质量正确但过度压缩的晶体结构,没有配合的分散校正.

结论:

开发的基准数据集为验证有机半导体计算方法提供了宝贵的资源.
r2SCAN-D3提供精确的几何形状,而PBE-D3提供了一个更快的替代方案,具有特定的限制.
大致的DFT方法需要仔细考虑分散校正,以准确预测单元细胞.

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