Single‐electron spodium bonds: Substituent effects

Abstract

This study performed a theoretical exploration to predict and characterize the single-electron spodium bond in the complexes of SpX 2 (Sp = Zn, Cd, and Hg; X = H, F, Cl, Br, and CH 3 ) with the H 3 C radical, in which the H 3 C radical serves as the Lewis base and the π-hole on the Sp atom in SpX 2 plays an acid role. The interaction energy varies in the range 7-30 kJ/mol, indicating that the Sp atom in SpX 2 has a good affinity for the H 3 C radical. The spodium bond strength is not only dependent on the size of the Sp atom of SpX 2 but is also affected by the substituent X in the Lewis acid. For most complexes, the spodium bond is stronger in the rank of Hg < Cd < Zn. The halogen substitution in SpX 2 strengthens the spodium bond, whereas a weakening effect is found for the CH 3 groups of Sp (CH 3 ) 2 . Regardless of the interaction intensity, the single-electron spodium bond exhibits the characteristics of a partially covalent interaction.

Strengthening of Noncovalent Bonds Caused by Internal Deformations

“…This insensitivity is likely due to the confluence of several factors. While the σ-hole of OsO 4 is weakened in 1b, the ES is compensated by the increased dipole moment of the Lewis acid and the closer approach of the two units. The changes in IND and DISP are fairly small, and in fact, one gets more negative and the other more positive, largely canceling out one another.…”

A Computational Chemistry Investigation of the Influence of Steric Bulk of Dithiocarbamato-Bound Organic Substituents upon Spodium Bonding in Three Homoleptic Mercury(II) Bis(N,N-dialkyldithiocarbamato) Compounds for Alkyl = Ethyl, Isobutyl, and Cyclohexyl

“…In the case of the zinc triad elements, the term "spodium bonding" applies [19]. This term is widely adopted, as revealed in subsequent systematic and computational chemistry studies [20][21][22][23][24][25][26][27][28], and, along with other Periodic Table Group-specific intermolecular interactions based on the σ-hole and π-hole concepts [29][30][31][32][33][34], spodium bonding is expected to be most prominent for the heavier Group 12 element, mercury.…”

“…Inorganics 2023, 11, x FOR PEER REVIEW 2 of 21 systematic and computational chemistry studies [20][21][22][23][24][25][26][27][28], and, along with other Periodic Table Group-specific intermolecular interactions based on the σ-hole and π-hole concepts [29][30][31][32][33][34], spodium bonding is expected to be most prominent for the heavier Group 12 element, mercury. Owing to the presence of two S atoms per dithiocarbamato anion and the inherent thiophilic character of Hg, the presence of Hg•••S interactions in crystals of mercury(II) dithiocarbamato compounds might very well be anticipated.…”