Bond paths show preferable interactions: ab initio and QTAIM studies on the X-H...pi hydrogen bond.
MP2/6-311++G(d,p) calculations on complexes of C(4)H(4), C(5)H(5)(-), and C(6)H(6), acting as Lewis bases, and C(2)H(2) and HF species, being Lewis acids, were carried out. Additionally the calculations were performed on C(3)H(3)(+)...C(2)H(2) and C(3)H(3)(+)...HF complexes. For the latter complexes, HF and C(2)H(2) molecules are Lewis bases while C(3)H(3)(+) ion is the Lewis acid. All systems were optimized, and no imaginary frequencies were found, showing that the complexes analyzed are energetic minima. The quantum theory of "atoms in molecules" (QTAIM) was also applied to analyze occurring interactions. The X-H...pi hydrogen bonds were found for complexes, except of those where C(3)H(3)(+) ion acts as the Lewis acid. QTAIM shows that for all systems analyzed the bond paths correspond to preferable interactions.
Kimika Fakultatea, Euskal Herriko Unibertsitatea and Donostia International Physics Center, P.K. 1072, 20080 Donostia, Euskadi Spain. s.grabowski@ikerbasque.org
Sławomir J
SJ
Grabowski
Jesus M
JM
Ugalde
D006219:Halogens / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory; D013816:Thermodynamics
D006219:Halogens