Theoretical Density Functional Theory insights into the nature of chalcogen bonding between CX₂ (X = S, Se, Te) and diazine from monomer to supramolecular complexes

Abstract

Chalcogen bonding is a noncovalent interaction, highly similar to halogen and hydrogen bonding, occurring between a chalcogen atom and a nucleophilic region. Two density functional theory (DFT) approaches B3LY‐D3 and B97‐D3 were performed on a series of complexes formed between CX2 (X = S, Se, Te) and diazine (pyridazine, pyrimidine and pyrazine). Chalcogen atoms prefer interacting with the lone pair of a nitrogen atom rather than with the π‐cloud of an aromatic ring. CTe2 and CSe2 form a stronger chalcogen bond than CS2. The electrostatic potential of CX2 (X = S, Se and Te) reveals the presence of two equivalent σ‐holes, one on each chalcogen atom. These CX2 molecules interact with diazine giving rise to supramolecular interactions. Wiberg bond index and second‐order perturbation theory analysis in NBO were performed to better understand the nature of the chalcogen bond interaction.

Ability of Lewis Acids with Shallow σ-Holes to Engage in Chalcogen Bonds in Different Environments

“…Such interactions are the domain of the elements of the main groups of the periodic table. The bonding terms triel (Group 13), tetrel [1][2][3] (Group 14), pnicogen [4,5] (Group 15), chalcogen [6,7] (Group 16), halogen [8,9] (Group 17), or aerogen (noble gas) atoms (Group 18) are used for elements that act as Lewis acids. Quite recently, a similar type of interaction has been studied for Group 2 elements [10] and for the transition metals of Groups 11 and 12 [11,12].…”

Nature of the Interaction of Pyridines with OCS. A Theoretical Investigation

“…These complexes involve the interaction of the XB...YZ type where Y possesses one or more electron pairs. They have been classified into halogen bonds where B is a halogen [5][6][7][8][9][10][11][12][13][14][15], chalcogen bonds where B = O, S, Se [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34], and more recently, tetrel bonds where B = C, Si [35][36][37][38][39][40][41][42]. These bonds are unusual in that they involve a close approach of two electronegative atoms such as Cl, O, C on the one hand, and Y atoms such as N on the other hand.…”

Influence of monomer deformation on the competition between two types of σ-holes in tetrel bonds

“…The concept of the σ-hole [19][20][21][22][23] , introduced with a view toward clarifying halogen bonding phenomenon [23][24][25][26][27][28][29][30][31] has been extended to a large family of noncovalent interactions where an electronegative atom is able to interact with a nucleophile. Although at first glance implausible, the attractive force is based on a local depletion of electron density around the halogen 32,33 , chalcogen 34,35 , pnicogen 36,37 , tetrel [38][39][40] or noble gas atoms [41][42][43][44] , usually directly opposite a σ-bond, hence its common appellation as a σ-hole. 45 Study over the years [46][47][48][49] has established that the strength of each σ-hole is enhanced by reduced electronegativity and enhanced polarizability of the central atom, coupled with electron-withdrawing power of its substituent.…”