Accurate Electronic Excitation Energies in Full-Valence Active Space via Bootstrap Embedding
Accurate Electronic Excitation Energies in Full-Valence Active Space via Bootstrap Embedding
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通过自举嵌入在全价活性空间中精确的电子激发能量
DOI：
10.1021/acs.jctc.0c01221
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发表时间：
2021
影响因子：
5.5
通讯作者：
Van Voorhis, Troy
中科院分区：
文献类型：
--
作者：
Ye, Hong-Zhou;Tran, Henry K.;Van Voorhis, Troy
碎片嵌入被广泛应用于避免使用精确的电子相关方法来描述分子和材料的电子基态的高计算尺度。然而，利用片段嵌入来处理电子激发态的类似应用在文献中较少报道。这里的挑战是双重的。首先，大多数片段嵌入方法在感兴趣的属性是局部的情况下是最有效的，但波函数在激励下的变化一般是非局部的。其次，即使是局部激励，由于需要对基态和激发态进行平衡处理，例如，对激发能的准确估计仍然是具有挑战性的。在这项工作中，我们证明了自举嵌入（BE），一种由我们小组最近开发的片段嵌入方法，有望描述一般的电子激发。数值模拟表明，对于局部激发和一些具有强电荷转移特征的大染料分子的激发，利用相对较小的片段，be可以很好地估计出全价活性空间（FVAS）的激发能，误差为~ 0.05 eV。因此，我们预期BE是一种很有前途的解决方案，可以准确地描述大型化学系统的激发态。
Fragment embedding has been widely used to circumvent the high computational scaling of using accurate electron correlation methods to describe the electronic ground states of molecules and materials. However, similar applications that utilize fragment embedding to treat electronic excited states are comparably less reported in the literature. The challenge here is twofold. First, most fragment embedding methods are most effective when the property of interest islocal, but the change of the wave function upon excitation isnonlocalin general. Second, even for local excitations, an accurate estimate of, for example, the excitation energy can still be challenging owing to the need for a balanced treatment of both the ground and the excited states. In this work, we show that bootstrap embedding (BE), a fragment embedding method developed recently by our group, is promising toward describing general electronic excitations. Numerical simulations show that the excitation energies in full-valence active space (FVAS) can be well-estimated by BE to an error of ∼0.05 eV using relatively small fragments, for both local excitations and the excitations of some large dye molecules that exhibit strong charge-transfer characters. We hence anticipate BE to be a promising solution to accurately describing the excited states of large chemical systems.