The dichalcogenides Ph2Ch2 (Ch = S, Se, Te) were cocrystallized with perfluorinated chalcogen bond donors TolF2Te and PyF2Te (TolF = 4-CF3C6F4, PyF = 4-NC5F4) to obtain the 1 : 1 cocrystals TolF2Te·Ph2Ch2 (Ch = S 1, Se 2, Te 3) and PyF2Te·Ph2Se2 (4). In the X-ray structures of 1-4, heterovalent TeII⋯ChI (Ch = S, Se, Te) chalcogen bonding was identified on consideration of the geometrical parameters and, in addition, based on the results of appropriate density functional theory (DFT) calculations including quantum theory of atoms-in-molecules (QTAIM), noncovalent interaction plot (NCIplot) analysis, molecular electrostatic potential surfaces (MEP), and atoms-in-molecules (AIM) charge analysis. The binding energy in the dimeric structure is in the range between −9.7 and −12.9 kcal mol−1, where the contribution of the heterovalent chalcogen bonding ranges from −4.7 to −6.5 kcal mol−1. In the TeII⋯ChI moiety, the TeII center plays the role of an electrophilic partner, while the chalcogens in the lower oxidation state, 1+, exhibit nucleophilic properties. The heterovalent TeII⋯ChI (Ch = Se, Te) chalcogen bonding was thus used for the targeted noncovalent integration of two Ch centers in different oxidation states.
ASJC Scopus subject areas
- Inorganic Chemistry