Charge-Sensitive Cluster−π Interactions Cause Altered Reactivity of Al_n^±,0 Clusters with Benzene: Enhanced Stability of Al₁₃⁺Bz

Abstract

Utilizing the homemade reflection time-of-flight mass spectrometer (Re-TOFMS), here we report a comprehensive study of the reactivity of aluminum clusters Al n ±,0 with molecular benzene in the gas-phase flow tube reactor. During the reactions with benzene, Al n + clusters were found to be relatively more reactive than Al n 0/–, and interestingly, the Al13 + cluster exhibited more reaction product than its neighboring Al n + clusters. With an emphasis on Al13 ±,0 clusters, we have performed an in-depth study utilizing DFT calculations to unravel the diverse reactivity of aluminum clusters with benzene. It is revealed that the Al13 +Bz cluster has a short Al–C distance and high binding energy, as well as an enlarged HOMO–LUMO gap in comparison with that of Al13 +. This contrasts with Al13 0/– and Al15 +, of which the HOMO–LUMO gaps are reduced when the cluster binds with a benzene molecule. Further, the cluster−π interactions between aluminum clusters and benzene are fully demonstrated via topological analysis, natural bonding orbital (NBO) analysis, and noncovalent interaction plots based on independent gradient model (IGM). The unique gyro-like structure of Al13 + and cluster−π interaction induce uneven redistribution of charges on the 13- atoms of Al13 +, enabling a tight Al–C bond with strong electrostatic attraction and orbital interactions, which largely differs from the weak orbital overlap and electrostatic repulsion between benzene molecule and Al13 0/– clusters.

Probing Cluster−π Interactions between Cun– and C2H2/C2H4 for Gas Separation

“…The ground-state structures for Cu n – ( n = 7–19) clusters are optimized by referring to our recent study on a basis of unbiased global search using the comprehensive genetic algorithm (CGA) code, combined with density functional theory (DFT) calculation based on DMol 3 package . B3LYP-D3­(BJ)/SDD basis set was used for Cu, while the 6-311+G­(d,p) was used for C and H atoms. ,, On the basis of the optimized ground-state structures, the total energies considering scalar-relativistic effect were calculated with zero-order regular approximation (ZORA) using the ADF program (version 2019.304). − The interactions and bonding nature between the Cu n – clusters and C 2 H 4 /C 2 H 2 molecule were calculated with the EDA-NOCV method . More details of the methods and a comparison of the experimental and calculated results including bond dissociation energies, adiabatic detachment energies (ADE), adiabatic ionization potential (AIP), and vibrational frequencies are given in the Supporting Information.…”

“…48 B3LYP-D3(BJ)/SDD basis set was used for Cu, while the 6-311+G(d,p) was used for C and H atoms. 35,49,50 On the basis of the optimized ground-state structures, the total energies considering scalar-relativistic effect were calculated with zero-order regular approximation (ZORA) using the ADF program (version 2019.304). 51−53 The interactions and bonding nature between the Cu n − clusters and C 2 H 4 /C 2 H 2 molecule were calculated with the EDA-NOCV method.…”

Remarkable static and dynamic nonlinear optical responses of Al13-TCNQ/F4-TCNQ complexes: a quantum chemical study

“…23 Additionally, many studies have been carried out on the adsorption of organic molecules (such as benzene, tetrahydrofuran, N-ethyl-2-pyrrolidone, and amino acid) on the Al 13 cluster. [24][25][26][27][28] Therefore, the Al 13 cluster can act as an electron acceptor to construct charge-transfer complexes. However, the charge is transferred from the Al surface to NH 2 NO 2 when the NH 2 NO 2 molecule is adsorbed on the Al 13 cluster.…”

Cyclotrimerization of Acetylene on Clusters Con+/Fen+/Nin+(n = 1–16)

“…Here, we report a study, performed with a homemade reflection time-of-flight mass spectrometer (Re-TOFMS), on the reactions of Fe n + , Co n + , and Ni n + clusters with acetylene in the gas phase and the observation of M + (C 6 H 6 ) production, shedding light on the cation−π interactions, − multimolecule synergistic effect, , and metal cluster catalysis.…”