We strongly condemn Russia's aggressive attack on Ukraine for which there is no rational justification. We stand firmly with the Ukrainian people.
Udo Buck and Burkhard Schmidt
Based on structure calculations of small ethene (C2H4) clusters published previously [R. Ahlrichs et al., Z. Phys. D. 15, 341, 1990], shifts and splittings of the fundamental excitation frequency of the ν7 mode are calculated for the dimer, trimer and tetramer. Using a first order perturbation approach, we find blue shifts in the order of 1-3 cm-1 which compare well with experimental findings. It is shown that the shifts are approximately independent of the cluster size and of the isomeric structure (ring-like or chain-like) of the ethene complexes.
J. Chem. Phys. 101 (7), 6365-6366 (1994)
DOI:10.1063/1.468392