Open AccessA Quantitative Molecular Orbital Perspective of the Chalcogen Bond
Author(s) -
Azevedo Santos Lucas,
Lubbe Stephanie C. C.,
Hamlin Trevor A.,
Ramalho Teodorico C.,
Matthias Bickelhaupt F.
Publication year - 2021
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.202000323
Subject(s) - chalcogen , natural bond orbital , chemistry , computational chemistry , hydrogen bond , density functional theory , molecular orbital , homo/lumo , covalent bond , chemical physics , crystallography , molecule , organic chemistry
We have quantum chemically analyzed the structure and stability of archetypal chalcogen‐bonded model complexes D 2 Ch⋅⋅⋅A − (Ch = O, S, Se, Te; D, A = F, Cl, Br) using relativistic density functional theory at ZORA‐M06/QZ4P. Our purpose is twofold: (i) to compute accurate trends in chalcogen‐bond strength based on a set of consistent data; and (ii) to rationalize these trends in terms of detailed analyses of the bonding mechanism based on quantitative Kohn‐Sham molecular orbital (KS‐MO) theory in combination with a canonical energy decomposition analysis (EDA). At odds with the commonly accepted view of chalcogen bonding as a predominantly electrostatic phenomenon, we find that chalcogen bonds, just as hydrogen and halogen bonds, have a significant covalent character stemming from strong HOMO−LUMO interactions. Besides providing significantly to the bond strength, these orbital interactions are also manifested by the structural distortions they induce as well as the associated charge transfer from A − to D 2 Ch.