Ab initio excitation spectrum of the CO-Ar van der Waals molecule

In the present contribution, we performed ab initio calculations at the CCSD(T) level of theory in the framework of the supermolecule approach on the weakly bound CO-Ar van der Waals (vdW) complex in its “near T-shaped” most-stable ground state structure. The corresponding vertical excitation energies from the ground CO(X1Σ)-Ar(1S) to the excited CO(A1Π)-Ar(1S) and CO(A3Π)-Ar(1S) states are calculated as a guideline for future theoretical and experimental work.