Aromaticity is one of the central concept in chemisty which leads to the stability of many cluseters with interesting structural motiff. Herein, a cationic BBe6H6 cluster featuring a planar hexacoordinate...

Quadruple bonding to main group elements is extremely rare although they have four valence orbitals accessible for bonding. Here we report the unprecedented quadruple bonding between carbon atom and a...

Unsupported donor–acceptor complexes of noble gases (Ng) with group 13 elements have been theoretically studied using density functional theory. Calculations reveal that heavier noble gases form thermodynamically stable compounds. The present study reveals that no rigid framework is necessary to stabilize the donor–acceptor complexes. Rather, prepyramidalization at the Lewis acid center may be an interesting alternative to stabilize these complexes. Detailed bonding analyses reveal the formation of two-center–two-electron dative bonding, where Ng atoms act as a donor.

Electronic structure and reactivity of a neutral Be(0) compound stabilized by N‐donor ligand L [L, bis(imidazolin‐2‐imine)], has been studied using density functional theory. The studied compound is found to have sufficient Be‐L bond dissociation energy. The electronic structure study reveals that this compound is isoelectronic with singlet carbenes. Topological analysis reveals the Be‐L bond to be of donor‐acceptor type. The presence of a rare Be…Hγ agostic interaction is also observed in the compound. The gas phase proton affinity of the compound is found to be very high (> 300 kcal/mol) and should be considered as “super basic”. The proton affinity of this compound (330‐334 kcal/mol) is found to be even higher than those of singlet carbenes. The promising ligating property with Lewis acid BH3 and BeCl2 has been noted. Its complex with BeCl2 is found to have very high bond dissociation energy with a strong Be−Be bond. Our computational results reveal that the proposed compound has the highest Lewis basicity among Be(0) compounds found in literature.

Planar pentacoordinate zinc group elements, (M = Zn, Cd, Hg) were computationally found to be at a global minimum in Li5M+ clusters. The stability of these clusters is due to the presence of multicentric bonds. The central element (Zn, Cd, Hg) in each cluster features a negative oxidation state owing to the in-plane electron donation by the Li5 + framework. A similar global minimum planar pentacoordinate structure is found in Na5Zn+ and Na5Cd+ clusters.

High-level quantum-chemical calculations have been used to predict a cationic ternary NBe5H4 + cluster containing a planar pentacoordinate nitrogen atom. The proposed cluster has pseudo dual aromaticity and is kinetically and thermodynamically very stable.

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The presence of a delocalized pi-bond is often considered an essential criterion for achieving planar hypercoordination. Herein, we show that sigma-delocalization could be sufficient to make the planar configuration the...