Earth-abundant Cr(III) polypyridines chromophores feature long-lived doublet ligand-field excited states. The thermally equilibrated 2 T 1 / 2 E ligand-field excited state manifold produces broad, structured UV-vis-NIR absorption bands. Although ubiquitous across pseudo-octahedral Cr(III) diimine...
Barth et al. (Thu,) studied this question.