Homo- and heterometallic complexes designed on group 11 metals and tris(6-methyl-2-pyridyl)phosphine: Synthesis, metallophilic interactions and room-temperature phosphorescence

Silver(I) Octanuclear Complexes Containing N′-(4-Oxotiazolidin-2-Iliden)picolinohydrazonamide and Nitrate as Bridge Ligands. An Example of Solvatomorphism?

“…This is true even in compound 3 , despite its long Ag···Ag distance (3.424 Å), where all four Ag-atoms are interconnected. The low magnitude of the electron density (0.010–0.031 au), positive values of the Laplacian of electron density (0.026–0.060 au), and negative energy density (from −0.0057 to −0.0304 au) in BCPs for short contacts Ag···Ag are typical for metallophilic interactions in similar chemical systems. , …”

“…The contour line diagrams of the Laplacian of electron density distribution ∇ 2 ρ­( r ), bond paths, visualization of electron localization function (ELF) and reduced density gradient (RDG) analyses for metallophilic interactions Ag···Ag are shown in Figure . These 2D maps along the QTAIM parameters at the BCPs evidence that the argentophilic interactions in the Ag 4 clusters of compounds 1 and 2 are akin to those in the isolated Ag 2 moieties and previously reported clusters . However, in compound 3 , one of the Ag···Ag interactions exhibits a higher electron density at the BCP (BCP “b,” ρ = 0.0315 au), indicating increased electron sharing between the Ag ions.…”

“…These 2D maps along the QTAIM parameters at the BCPs evidence that the argentophilic interactions in the Ag 4 clusters of compounds 1 and 2 are akin to those in the isolated Ag 2 moieties and previously reported clusters. 64 However, in compound 3 , one of the Ag···Ag interactions exhibits a higher electron density at the BCP (BCP “b,” ρ = 0.0315 au), indicating increased electron sharing between the Ag ions. Consequently, due to the strengthening of the Ag1···Ag2 (and symmetrically equivalent Ag4···Ag3) interaction, the Ag1···Ag4 bond weakens (BCP “a,” ρ = 0.0102 au) and becomes clearly noncovalent, as indicated by the positive value of the total energy density ( H ) and the reduced ELF at the Ag1···Ag4 BCP (see Figure 14 ).…”

“…The low magnitude of the electron density (0.010−0.031 au), positive values of the Laplacian of electron density (0.026−0.060 au), and negative energy density (from −0.0057 to −0.0304 au) in BCPs for short contacts Ag•••Ag are typical for metallophilic interactions in similar chemical systems. 63,64 The balance between the Lagrangian kinetic energy G(r) and potential energy density V(r) at the BCPs for metallophilic interactions in all BCPs apart from "a" in 3 reveals noticeable covalent contribution in all these short contacts. 65 The Laplacian of electron density can be decomposed into the sum of contributions along the three principal axes of maximal variation, giving the three eigenvalues of the Hessian matrix (λ 1 , λ 2 , and λ 3 ), and the sign of λ 2 can be utilized to distinguish bonding (attractive, λ 2 < 0) weak interactions from nonbonding ones (repulsive, λ 2 > 0).…”