Capturing the interplay between spin-orbit coupling and non-Condon effects on the photoabsorption spectra of Ru and Os dyes.

In this work, we investigate the factors influencing the shape of the low-energy tail of the absorption spectrum of a homoleptic biscyclometalated ruthenium complex with terdentate ligands [Rees et al., Inorganic Chemistry, 2017, 56, 9903] by combining an advanced theoretical strategy and the synthesis of an analogous Osmium complex. The theoretical protocol merges relativistic linear-response time-dependent density functional theory and the nuclear ensemble approach, permitting to shed light on the influence of spin-orbit coupling and non-Condon effects on the theoretical absorption spectra of these rather large metal complexes