RETRACTED: DFT challenge of intermetallic interactions: From metallophilicity and metallaromaticity to sextuple bonding

et al. 2021

Chem. Sci.

Section: Resultsmentioning

confidence: 65%

Aggregation-induced phosphorescence sensitization in two heptanuclear and decanuclear gold–silver sandwich clusters

Lü

et al. 2021

Chem. Sci.

“…In this work, the overall intermolecular interaction of d 8 /d 10 complexes is decomposed into the London dispersion (E Disp ) (22,50,51), electrostatic interaction (E Elst ), orbital interaction (E Orb ) (27)(28)(29), and Pauli repulsion (E Pauli ) (32). Each of these terms could be further decomposed into interfragment interactions, namely, the metal-metal interaction (M-M′), intermolecular metal-ligand interaction (M-L′/M′-L), ligand-ligand interaction (L-L′), and intramolecular metal-ligand interaction (M-L).…”

mentioning

confidence: 99%

Strong metal–metal Pauli repulsion leads to repulsive metallophilicity in closed-shell d⁸and d¹⁰organometallic complexes

Wan

Proc. Natl. Acad. Sci. U.S.A.

et al. 2020

Metallophilicity is defined as the interaction among closed-shell metal centers, the origin of which remains controversial, particularly for the roles of spd orbital hybridization (mixing of the spd atomic orbitals of the metal atom in the molecular orbitals of metal complex) and the relativistic effect. Our studies reveal that at close M–M′ distances in the X-ray crystal structures of d8 and d10 organometallic complexes, M–M′ closed-shell interactions are repulsive in nature due to strong M–M′ Pauli repulsion. The relativistic effect facilitates (n + 1)s-nd and (n + 1)p-nd orbital hybridization of the metal atom, where (n + 1)s-nd hybridization induces strong M–M′ Pauli repulsion and repulsive M–M′ orbital interaction, and (n + 1)p-nd hybridization suppresses M–M′ Pauli repulsion. This model is validated by both DFT (density functional theory) and high-level coupled-cluster singles and doubles with perturbative triples computations and is used to account for the fact that the intermolecular or intramolecular Ag–Ag′ distance is shorter than the Au–Au′ distance, where a weaker Ag–Ag′ Pauli repulsion plays an important role. The experimental studies verify the importance of ligands in intermolecular interactions. Although the M–M′ interaction is repulsive in nature, the linear coordination geometry of the d10 metal complex suppresses the L–L′ (ligand–ligand) Pauli repulsion while retaining the strength of the attractive L–L′ dispersion, leading to a close unsupported M–M′ distance that is shorter than the sum of the van der Waals radius (rvdw) of the metal atoms.

“…Although metallophilic interactions have been investigated with a series of quantum chemical methods, the size of the systems studied renders the use of more computationally expensive methods prohibitive and unfeasible [ 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. The B3LYP [ 45 , 46 , 47 ], M06-2X [ 48 ], ω B97XD [ 49 ], B3LYP-D3 [ 50 , 51 ], PBE0 [ 52 , 53 ,], and MP2 [ 54 , 55 ] methods were employed respectively to optimize the polymeric ground-state geometries of clusters X ( X = I , II , and III , see Figure 1 ) on the basis of the experimental X-ray structures.…”

Section: Computational Methodologymentioning

confidence: 99%

Phosphorescent Modulation of Metallophilic Clusters and Recognition of Solvents through a Flexible Host-Guest Assembly: A Theoretical Investigation

et al. 2018

Nanomaterials

MP2 (Second order approximation of Møller–Plesset perturbation theory) and DFT/TD-DFT (Density functional theory/Time-dependent_density_functional_theory) investigations have been performed on metallophilic nanomaterials of host clusters [Au(NHC)2]+⋅⋅⋅[M(CN)2]−⋅⋅⋅[Au(NHC)2]+ (NHC = N-heterocyclic carbene, M = Au, Ag) with high phosphorescence. The phosphorescence quantum yield order of clusters in the experiments was evidenced by their order of μS1/ΔES1−T1 values (μnormalS1: S0 → S1 transition dipole, ∆EnormalS1−normalT1: splitting energy between the lowest-lying singlet S1 and the triplet excited state T1 states). The systematic variation of the guest solvents (S1: CH3OH, S2: CH3CH2OH, S3: H2O) are employed not only to illuminate their effect on the metallophilic interaction and phosphorescence but also as the probes to investigate the recognized capacity of the hosts. The simulations revealed that the metallophilic interactions are mainly electrostatic and the guests can subtly modulate the geometries, especially metallophilic Au⋅⋅⋅M distances of the hosts through mutual hydrogen bond interactions. The phosphorescence spectra of hosts are predicted to be blue-shifted under polar solvent and the excitation from HOMO (highest occupied molecular orbital) to LUMO (lowest unoccupied molecular orbital) was found to be responsible for the 3MLCT (triplet metal-to-ligand charge transfer) characters in the hosts and host-guest complexes. The results of investigation can be introduced as the clues for the design of promising blue-emitting phosphorescent and functional materials.