Aromaticity of [M3(µ‐X)3X6]0/2– (M = Re and Tc, X = Cl, Br, I) Clusters Confirmed by Ring Current Analysis and Induced Magnetic Field

• Published in: European journal of inorganic chemistry 2018-07, Vol.2018 (28), p.3312-3319
• Main Authors: Rabanal‐León, Walter A., Vásquez‐Espinal, Alejandro, Yañez, Osvaldo, Pino‐Rios, Ricardo, Arratia‐Pérez, Ramiro, Alvarez‐Thon, Luis, Torres‐Vega, Juan J., Tiznado, William
• Format: Article
• Language: English
• Subjects: Aromaticity; Chemical bonds; Clusters; Induced magnetic field; Inorganic chemistry; Magnetic fields; Magnetic properties; Magnetism; Metal clusters; Organic chemistry; Ring current density; Ring currents
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.201800339

We present new evidence that supports the aromatic character of the clusters of formula: [M3(µ‐X)3X6]0/2– (M = Re and Tc, X = Cl, Br, I). Our computations clearly show that these clusters present a special response to an applied external magnetic field, which is characteristic of aromatic systems. Both analyzed response properties, the magnetically induced current density and the induced magnetic field, agree that the magnetic perturbation induces two concentric diatropic ring currents: the inner one inside the M3 core and the outer one around the M3(µ‐X)3 triangle. The flow strength of these two ring currents is significant, confirming the high diatropicity of these clusters. In the dianionic species, aromaticity is increased, mainly by an increment of the diatropicity of the inner ring current. These findings support a chemical bonding pattern with delocalized M–M bonds in these species. New computational evidence, based on magnetic response, clearly shows that [M3(µ‐X)3X6]0/2– (M = Re and Tc, X = Cl, Br, I) clusters are strongly aromatic. These findings support a chemical bonding pattern with delocalized M–M bonds in these species.