Isotope Effects on XH<middle dot><middle dot><middle dot>C20 (X = F, Cl, Br) Systems: A Quantum Chemistry Approach

In this work, we optimized XH<middle dot><middle dot><middle dot>C-20 (X = F, Cl, Br) systems at the LC-omega PBE /6-311G(d,p) level of theory and illustrated structural, electronic and vibrational properties in these systems. The relative stabilities of the D-containing isotopomers (XD<middle dot><middle dot><middle dot>C-20) and XH<middle dot><middle dot><middle dot>C-20 systems were compared. Bond critical point of C<middle dot><middle dot><middle dot>H interactions were clarified by quantum theory of atoms in molecules (QTAIM) calculations. Binding energy of hydrogen bonds were computed based on electron density at BCP of H-bond. Charge decomposition analysis (CDA) was considered to understanding of the electron transfer between XH and C-20 molecules. Reduced density gradient (RDG) was used to analyze the C<middle dot><middle dot><middle dot>X interactions.