Stabilization of Zn group dimers: A theoretical study

Abstract

Quantum chemical calculations have been carried out to investigate the possibility of Group 12 (Zn, Cd, Hg) dimer formation supported by the B3 ring. All these complexes have significantly shorter M‐M (M = Zn, Cd, Hg) distances compared to their bare dimers, M2. The staggered and eclipsed forms of these complexes were found to be nearly degenerate. They have significant bond strengths as revealed from the significantly higher values of Wiberg bond indices as well as bond dissociation energies. The topological feature of electron density reveals significant covalency in the M‐M interaction which has also been confirmed from natural orbital for chemical valence analysis coupled with extended transition state (ETS‐NOCV) calculations.

Structure, stability and reactivity of inverse sandwich complexes M‐Be3‐M and M‐Zn3‐M (M = Li, Na, K, Cu, Ag, Au)

“…Similar situation is also observed for the present inverse sandwich complexes. This implies that BeM and ZnM bonds of the current inverse sandwich complexes have acquired the similar nature with the MM bond studied earlier [51]. The negative ratio of G(r) and V(r) also indicates the existence of covalency in bonding [52, 53].…”

“…This implies that Be M and Zn M bonds of the current inverse sandwich complexes have acquired the similar nature with the M M T A B L E 3 HOMO-LUMO gap (Δ H-L ) in eV and interaction energy (IE, kcal mol À1 ) of the studied systems calculated using M06-2X/def2-TZVP level and CCSD(T)/def2-TZVP level of Be 3 M 2 and Zn 3 M 2 complexes. bond studied earlier [51]. The negative ratio of G(r) and V(r) also indicates the existence of covalency in bonding [52,53].…”

“…Recently, we theoretically investigated some bimetallic sandwich complexes of the type B 3 ‐M‐M‐B 3 (M = Zn, Cd and Hg) where we analyzed the MM bond critical point (BCPs) to determine the nature of the bonds [51]. Additionally, we found that the MM bond had a polar covalent character with positive ∇ 2 ρ values and negative H (r) values [51]. Similar situation is also observed for the present inverse sandwich complexes.…”

“…For a polar covalent nature of a bond, r 2 ρ should be positive and H(r) should be negative [48]. Recently, we theoretically investigated some bimetallic sandwich complexes of the type B 3 -M-M-B 3 (M = Zn, Cd and Hg) where we analyzed the M M bond critical point (BCPs) to determine the nature of the bonds [51]. Additionally, we found that the M M bond had a polar covalent character with positive r 2 ρ values and negative H(r) values [51].…”