π-Stacking Isomerism in Polycyclic Aromatic Hydrocarbons: The 2-Naphthalenethiol Dimer.

ABSTRACT: π-Stacking is a common descriptor for face-to-face attractive forces between aromatic hydrocarbons. However, the physical origin of this interaction remains debatable. Here we examined π-stacking in a model homodimer formed by two thiol-substituted naphthalene rings. Two isomers of the 2-naphthalenethiol dimer were discovered using rotational spectroscopy, sharing a parallel-displaced crossed orientation and absence of thiol-thiol hydrogen bonds. One of the isomers presents C₂ symmetry, structurally analogous to the global minimum of the naphthalene dimer. The experimental data were rationalized with molecular orbital calculations, revealing a shallow potential energy surface. Noncovalent interactions are dominated by dispersion forces according to SAPT energy decompositi

SUBMITTER: Saragi RT 

PROVIDER: S-EPMC9841560 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature