THE AB INITIO CALCULATION OF THE $C_{3}$ - AR VAN DER WAALS COMPLEX

Abstract

The equilibrium geometry of the ground electronic state of $C_{3}Ar$ has been determined to be T-shaped at the level of CCSD(T)/cc-pVQZ: $\ell(C - C)=1.298{\AA}, \angle C - C - C=173.75^{\circ}, \ell(C_{3} - Ar)=3.85{\AA}, \angle C_{3} - Ar = 90^{\circ}$. Its binding energy is about $130 cm^{-1}$ and the vdW stretch is $30 cm^{-1}$. The internal rotation of the complex is strongly coupled with the vdW stretch. Other conformers (two in-plane and one out-of-plane) have been identified as the $C_{3}$ moiety of the complex bends away from the equlibrium angle. The computation results will be used to qualitatively interpret our experimental observations.