Harmonic Oscillator Model of Aromaticity for Organometallics Containing the Os–C Bond

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.