Aromaticity is an important concept in chemistry with multidimensional properties, attracting considerable attention from both experimental and computational chemists. Among various aromaticity indices, the harmonic oscillator model of aromaticity (HOMA) is a reliable aromaticity criterion with a negligible computational cost based on the geometry (bond distance). However, the HOMA parameters for organometallic aromatics are not available. Here, we develop the Os–C bond parameter of HOMA by theoretical calculations. Its reliability in evaluating aromaticity is supported by its good correlation against other aromaticity indices, including the electron density of delocalized electrons and bond order difference, with R2 values ranging from 0.74 to 0.77. Our finding might be particularly helpful for chemists to evaluate the aromaticity in organometallics based on their geometries.

https://doi.org/10.1021/acs.organomet.3c00257