Ab initio calculations have been performed for a series of binuclear sandwich complexes, M₂(η⁵-L)₂. It has been observed that the eclipsed and staggered conformations have almost equal amount of energies. The M–M bond lengths are comparable with those in the free M₂ molecules (M = Be, Mg). The nuclear-independent chemical shift (NICS) values indicate the aromaticity of these complexes. The stability of Be₂(η⁵-L)₂ complexes is higher than that of the Mg₂(η⁵-L)₂ complexes. The natural bond orbital (NBO) analysis and electron density descriptors proved the existence of a single covalent M–M bond in an M₂²⁺ fragment. It has been observed that each M–M bond contains a non-nuclear attractor (NNA) at the center of the respective bond. The Laplacian of electron density [∇²ρ(r)] is negative at the NNAs. The energy decomposition analysis (EDA) showed that M₂²⁺ and 2L^– represent the bonding interaction in the complexes. All of the designed binuclear sandwich complexes behave as electrides.

中文翻译：

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一些双核夹心碱土金属的配合物，M的电子化合物特性₂（η ⁵ -L）₂（M =铍，镁; L = c ^ ₅ ħ ₅ ^-，N ₅ ^-，P ₅ ^- ，如₅ ^- ）

从头计算已经进行了一系列的双核夹心复合物的执行中，M ₂（η ⁵ -L）₂。已经观察到，黯淡和交错的构象具有几乎相等的能量。M–M键的长度与游离M ₂分子中的键长度相当（M = Be，Mg）。不依赖核的化学位移（NICS）值表明这些配合物的芳香性。的是稳定性₂（η ⁵ -L）₂配合物是比镁更高的₂（η ⁵ -L）₂复合体。天然键轨道（NBO）分析和电子密度描述符证明了M ₂ ²⁺片段中存在单个共价M–M键。已经观察到，每个M–M键在相应键的中心都包含一个非核吸引子（NNA）。电子密度的拉普拉斯[∇ ² ρ（[R）]是在NNAs负。能量分解分析（EDA）表明，中号₂ ²⁺和2L ^-表示在复合物中的键合相互作用。所有设计的双核三明治复合物均表现为电子。