Can boron form coordination complexes with diffuse electrons? Evidence for linked solvated electron precursors
Can boron form coordination complexes with diffuse electrons? Evidence for linked solvated electron precursors
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DOI：
10.1088/2516-1075/ac495c
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发表时间：
2022-03-01
影响因子：
2.6
通讯作者：
Miliordos, Evangelos
中科院分区：
文献类型：
--
作者：
Jordan, Zachary;Khan, Shahriar N.;Miliordos, Evangelos
采用密度泛函理论和从头计算方法研究了硼配合物的稳定性和电子结构。这种配合物（溶剂化电子前体或SEP）已被实验确定，并在理论上研究了几个S-和D-块金属。我们首次证明了当选择合适的配体时，p-区类金属元素可以形成稳定的SEP。我们发现，三个氨和一个甲基配体可以取代两个三个硼价电子的外围1 s型轨道。这些外层电子的壳层模型与以前的SEP系统（1 s，1 p，1d，2s）相同。此外，我们进行了第一次检查的分子系统组成的两个SEP桥接的烃链。这些二聚体的电子结构与传统的形成成键和反键σ和π轨道的双原子分子的电子结构非常相似。它们的基态电子结构类似于两个He原子的基态电子结构，并且我们的结果表明，对于四个碳原子或更长的碳原子，激发能几乎与链长无关。这些发现为开发类似于金属网和金属网的新型材料铺平了道路。
Density functional theory and ab initio multi-reference calculations are performed to examine the stability and electronic structure of boron complexes that host diffuse electrons in their periphery. Such complexes (solvated electron precursors or SEPs) have been experimentally identified and studied theoretically for several s- and d-block metals. For the first time, we demonstrate that a p-block metalloid element can form a stable SEP when appropriate ligands are chosen. We show that three ammonia and one methyl ligands can displace two of the three boron valence electrons to a peripheral 1s-type orbital. The shell model for these outer electrons is identical to previous SEP systems (1s, 1p, 1d, 2s). Further, we preformed the first examination of a molecular system consisting of two SEPs bridged by a hydrocarbon chain. The electronic structure of these dimers is very similar to that of traditional diatomic molecules forming bonding and anti-bonding sigma and pi orbitals. Their ground state electronic structure resembles that of two He atoms, and our results indicate that the excitation energies are nearly independent of the chain length for four carbon atoms or longer. These findings pave the way for the development of novel materials similar to expanded metals and electrides.