BeO analogues of annulated cyclooctatetraene and cyclodecapentaene as new inorganic species with unusual multiple hypervalent O∙∙∙O interactions

Density functional theory calculations at the level of B3LYP/6-311+G(df,p) and wB97XD/6-311+G(df,p) predict stability of the BeO analogues of annulated cyclooctatetraene and cyclodecapentaene, Be_nO_nH_n (n = 8, 10), which uniquely feature the presence of multiple hypervalent diagonal O∙∙∙O interactions within the four-membered rings.