			15min:

STRUCTURES AND SPECTROSCOPIC PROPERTIES CALCULATED FOR C₆H₇⁺ AND ITS COMPLEXES WITH Ne, Ar, N₂, OR CO₂.

P. BOTSCHWINA AND R. OSWALD, Institute of Physical Chemistry, University of Göttingen, \- Tammannstr. 6, D-37077 Göttingen, Germany.

Explicitly correlated coupled cluster theory at the CCSD(T)-F12x (x = a, b) level\footnoteT.~B.~Adler, G.~Knizia, and H.-J.~Werner, J.~Chem.~Phys. \underline\textbf127, 221106 (2007);
\hspace*0.45cm G.~Knizia, T.~B.~Adler, and H.-J.~Werner, J.~Chem.~Phys. \underline\textbf130, 054104 (2009). in conjunction with the double-hybrid density functional B2PLYP-D has been employed in a study of the benzenium ion (C₆H₇⁺) and its complexes with simple ligands (L = Ne, Ar, N₂, or CO₂).\footnoteP.~Botschwina and R.~Oswald, J.~Phys.~Chem.~A \underline\textbf115, 13664 (2011);
\hspace*0.45cm P.~Botschwina and R.~Oswald, J.~Chem.~Phys. submitted. The ground-state rotational constants of C₆H₇⁺ are predicted to be A₀ = 5445 MHz, B₀ = 5313 MHz, and C₀ = 2731 MHz. For the complexes with L = Ne, Ar or N₂, the energetically most favourable structure is of -bonded type, but for the most strongly bound complex C₆H₇⁺ cdot CO₂ a conformer with the CO₂ ligand lying in the ring-plane of the C₆H₇⁺ moiety is slightly lower in energy.