Elusive structures of Cu clusters mapped with FELIX far-infrared spectroscopy

Scientists often use metal clusters as well-defined model systems, to gain a better understanding of molecular mechanisms in reactions. Knowledge of the clusters, and in particular of their structures, is of crucial importance.

Despite the fact that Cu clusters were among the first clusters produced in the 1980s, the available structural information is limited. FELIX researchers Olga Lushchikova and Joost Bakker filled this gap by recording the infrared spectra of Cu_n⁺ clusters in the 70-280 cm^-1 spectral range. FELIX is the only instrument worldwide capable of delivering sufficiently intense radiation at the long wavelengths characteristic for the infrared signatures of metal clusters.

The new knowledge is indispensable for researchers in the fields of heterogeneous catalysis, solid-state physics, surface chemistry and organometallic chemistry. The catalytic activity of, for instance, the industrial CO₂ hydrogenation catalyst has been largely attributed to copper nanoparticles on an Al₃O₄ surface. Using the now revealed information, scientists can more rigorously test proposed reaction pathways, potentially helping the design of novel, higher activity catalysts.

Reference:
Lushchikova, O. V; Huitema, D. M. M.; López-Tarifa, P.; Visscher, L.; Jamshidi, Z.; Bakker, J. M., Structures of Cu_n⁺ (n = 3–10) Clusters Obtained by Infrared Action Spectroscopy,  J. Phys. Chem. Lett. 2019, 2151–2155.

More information:
Joost Bakker