Search

The hexagonal and heptagonal holes of B 39 - allow its complexation with a half sandwich complex ECp∗+ (E Si, Ge, Sn, Pb). Structure and the nature of bonding of (η6/7-B39)E(η5-Cp∗) are explored through the density functional theory based computation. (η6-B39)E(η5-Cp∗) isomers are more stable than (η7-B39)E(η5-Cp∗) and the energy difference between these two isomers decreases down the group from Si to Pb. The dissociation path, (η6/7-B39)E(η5-Cp∗) → B 39 - + ECp∗+ is studied. For all E, (η6/7-B39)E(η5-Cp∗) is formed exergonically at 298 K temperature as given by the ΔG values of dissociation path [60.1(Si) to 68.3(Pb) kcal/mol for (η6-B39)E(η5-Cp∗) and 58.3(Si) to 67.8(Pb) kcal/mol for (η7-B39)E(η5-Cp∗)]. The adduct becomes bent around the central E atom when B 39 - gets attached to ECp∗+ and the amount of bending increases gradually down the group from Si to Pb. Bonding analysis of the stable isomer, (η6-B39)E(η5-Cp∗) has been done by natural bonding orbital (NBO) and energy decomposition analyses (EDA). The electron density from B 39 - is transferred to the ECp∗+ moiety as revealed by the NBO analysis. All the complexes are mainly stabilized by the electrostatic and orbital interactions between B 39 - and ECp∗+ fragments as highlighted by the EDA results.

The activation of allene by a five-membered P/B frustrated Lewis pair (FLP) has been explored by DFT based computational study. It reveals the addition of allene to the FLP takes place via two thermodynamically favorable path. But, the attack of the P center of the FLP to the middle carbon of allene is kinetically more preferable. The reaction is further analysed by taking methyl-allene and cyano-allene and which produce four thermodynamically favorable regioisomers. However the attack of the P center of the FLP to the middle carbon is kinetically more preferable. The mechanism of the reactions are carefully analysed.

An in silico analysis is performed to check the hydrogen storage potential of (HF)m (m = 1–8) and (H2O)n (n = 1–10) clusters. Each HF unit in (HF)m cluster can bind three H2 molecules whereas each H2O unit in (H2O)n can adsorb one hydrogen molecule (excluding H2O and (H2O)2). It is found that conceptual density functional theory based reactivity descriptors can explain the stability of molecular hydrogen adsorbed (HF)m (m = 1–8) and (H2O)n (n = 1–10) clusters. The nature of interaction between (HF)m/(H2O)n cluster and the adsorbed H2 molecules is studied using electron density based descriptors. Energy decomposition analysis is carried out to assess the type of interaction between the molecular clusters and adsorbed hydrogen molecules. Ab initio molecular dynamics (AIMD) simulation is also carried out using an atom centered density matrix propagation (ADMP) technique to predict the kinetic stability of hydrogen adsorbed (HF)m and (H2O)n analogues in a one picosecond time scale.