Theory and Modeling of the Binding in Cationic Transition-Metal−Benzene Complexes

Abstract

Binding energies are estimated for the complexes of benzene with the first-row transition-metal ions (M+ = Ti+−Cu+) via both kinetic modeling and quantum chemical simulation. A variational transition-state theory model implementing an ion−quadrupole plus ion-induced dipole potential is employed in the modeling of the kinetic data for the collision-induced dissociation of these complexes. For Cr+, a global potential is generated for its interaction with benzene and radiative association experiments are also modeled. Implementation of this potential in the transition-state analyses indicates only minor anharmonicity effects for the complex state density near the dissociation threshold and negligible deviation from the long-range potential-based predictions for the transition-state partition functions. Theoretical optimized geometries, binding energies, and vibrational frequencies are determined with the B3LYP (Becke-3 Lee−Yang−Parr) density functional. The V+, Ni+, and Fe+ complexes are found to have modest Jahn−Teller-induced boat-shaped distortions of the benzene ligand. The quantum chemical and kinetic modeling based estimates for the binding energies are in reasonable agreement.

Interactions of Atomic Iron Cation with Pyridine and Benzene: A Theoretical Study on an Unresolved Controversy of Bond Energies and Electronic Ground‐State Structures

“…In agreement with previous work [22], this produces a boat-shaped ligand with the twofold C-atoms bending toward the metal ion and slightly increased CÀC bond lengths. The CCCC dihedral angle amounts to 68.…”

“…Armentrout and co-workers obtained a threshold-CID value of 207.5 AE 9.6 kJ mol À1 [17] [21]. In a kinetic modelling study of Yang and Klippenstein [22], the best estimate for BDE(Fe Àbz) is a variable-reaction-coordinate transition-state theory (VRC-TST) value of 208.8 kJ mol…”

Binding Energies of Gas-Phase Metal Ions with Pyrrole: Experimental and Quantum Chemical Results

“…20 All of the quantum chemical calculations reported here were performed with the GAUSSIAN94 software. 15 Kinetic Modeling.…”

Studies on electronic structures, energetics, and electron affinities of transition metal–benzene complexes and their anions with density functional theory

“…On the theoretical aspect, the efforts in 3d transition meal interacting with benzene molecules have been carried out to understand the geometry, dissociation energy, ionization potentials, electron affinities, electron configuration and spin multiplicities etc. [17][18][19][20][21][22][23][24][25][26][27]. Jena and coworkers [17] found V n (benzene) m complexes clearly prefer sandwich structures to rice-ball structures and their ground state spin multiplicities increased linearly with the size of the system.…”