Ternary 14-electron XB2Be2 (X = Si, Ge, Sn, Pb) clusters: a planar tetracoordinate silicon (ptSi) system and its ptGe/Sn/Pb congenersElectronic supplementary information (ESI) available: Cartesian coordinates for GM clusters XB2Be2 (X = Si/Ge/Sn/Pb) (1–4) at the PBE0-D3/def2-QZVP level (Table S1); orbital composition analyses for SiB2Be2 (1) and PbB2Be2 (4) clusters (Tables S2 and S3); top lowest-lying structures and their relative energies (Fig. S1); Wiberg bond indices (WBIs) and natural atomic charges for clusters 1–4 (Fig. S2); comparative root-mean-square deviations (RMSDs) of cluster 1 during the BOMD simulations at room temperature (298 K) and at a higher temperature (1200 K) (Fig. S3); and canonical molecular orbitals (CMOs), AdNDP bonding scheme, as well as electron localization function (ELF) analysis of cluster 4 (Fig. S4 and S5). See DOI: 10.1039/d1cp05226h

Ternary 14-electron XB2Be2 (X = Si, Ge, Sn, Pb) clusters: a planar tetracoordinate silicon (ptSi) system and its ptGe/Sn/Pb congenersElectronic supplementary information (ESI) available: Cartesian coordinates for GM clusters XB2Be2 (X = Si/Ge/Sn/Pb) (1–4) at the PBE0-D3/def2-QZVP level (Table S1); orbital composition analyses for SiB2Be2 (1) and PbB2Be2 (4) clusters (Tables S2 and S3); top lowest-lying structures and their relative energies (Fig. S1); Wiberg bond indices (WBIs) and natural atomic charges for clusters 1–4 (Fig. S2); comparative root-mean-square deviations (RMSDs) of cluster 1 during the BOMD simulations at room temperature (298 K) and at a higher temperature (1200 K) (Fig. S3); and canonical molecular orbitals (CMOs), AdNDP bonding scheme, as well as electron localization function (ELF) analysis of cluster 4 (Fig. S4 and S5). See DOI: 10.1039/d1cp05226h