Ternary 14-electron XB₂Be₂ (X = Si, Ge, Sn, Pb) clusters: a planar tetracoordinate silicon (ptSi) system and its ptGe/Sn/Pb congeners

Abstract

The ternary SiB2Be2 cluster is a planar tetracoordinate silicon (ptSi) system and features 2π/2σ double aromaticity. Its 14-electron count deviates from the 18-electron rule.

Ternary XBe4H5− (X = Si, Ge, Sn, Pb) Clusters: Planar Tetracoordinate Si/Ge/Sn/Pb Species with 18 Valence Electrons

“…In 2016, Ding reported a series of planar tetracoordinate group 14 atom species C 2 Si 2 X q (X = C, Si, Ge, Sn, Pb; q = +1, 0, −1) [ 33 ]. In 2022, a class of ternary 14ve clusters, ptSi/Ge/Sn/Pb XB 2 Be 2 (X = Si, Ge, Sn, Pb), were computationally predicted by Zhai [ 34 ]. It should be noted that the global minima of XMg 4 Y (X = Si, Ge; Y = In, Tl) and SiMg 3 In 2 clusters were predicted by Cui and coworkers, which represent the first series of ppSi/Ge clusters [ 35 ].…”

Ligand-enforced geometric constraints and associated reactivity in p-block compounds

“…Despite early calculations showing the lower energy barrier required for the planarization of four-coordinate silicon species compared to carbon, experimental realization of planarization for the heavier group 14 elements has only occurred recently. 77,90–111…”

XB2Bi2 (X = Si, Ge, Sn, Pb): Penta-Atomic Planar Tetracoordinate Si/Ge/Sn/Pb Clusters with 20 Valence Electrons

“…Two years later, Xu reported nine penta-atomic ptSi GMs with 14 VEs, including Li 3 SiAs 2− , HSiY 3 (Y = Al/Ga), Ca 3 SiAl − , Mg 4 Si 2 − , C 2 LiSi, and Si 3 Y 2 (Y = Li/Na/K) [ 42 ]. Recently, the ptX XB 2 Be 2 (X = Si, Ge, Sn, Pb) clusters were designed, each of which has 14 VEs [ 43 ]. In 2014, a series of ptX GMs, C 2 Si 2 X q (X = C, Si, Ge, Sn, Pb; q = +1, 0, −1), with 19/20/21 VEs, were predicted by Ding [ 44 ].…”