ABSTRACT Oligomerization of (CO) n ( n = 2–6) clusters initiated by mechanical pressure has been investigated using quantum chemical methods at TPSSTPSS‐D3/aug‐cc‐pVTZ level. The clusters were confined within He@60 (for dimer) and He@180 cages (for trimer to hexamer), and mechanical pressure up to 18.9 GPa was exerted on the clusters by gradually decreasing cage volume. A total of 29 distinguishable conformers, 2, 4, 10, 11, and 2 for dimers, trimers, tetramers, pentamers, and hexamers, respectively, have been studied. Dimerization was found to initiate at a considerably higher pressure of 18.9 GPa, compared to the larger clusters at ≤ 1.6 GPa. Ten distinct and stable oligomers were obtained bound by a variety of covalent linkages (CC, CC, CO, CCO, CCC, COC, etc.), all of which have been experimentally identified. Atom in molecules analyses have been used to confirm the formation of all covalent linkages in the formed CO oligomers.
Oram et al. (Thu,) studied this question.