The heretofore unknown ernission properties :of the,metal-to-ligand charge-transfer (MLCT) excited states of several complexes with (ruthenium)(monodentate aromatic ligand, MDA) chromophores are given. Emission spectra and lifetimes in 77 K glasses are reported for several monometallic complexes of the type [Ru(NH3)(5-n)(L)(n) (MDA)](2+) and two bimetallic pyrazine (pz)- bridged [{Ru(NH3)(4-n)(L)(n)}(2)pz](4+) complexes (L = pz, pyridine, or a multipyridine ligarid; MDA = pz or a substituted pyridine, Y-py): The emission maxima occur in the visible and near-IR spectral regions and have much more poorly resolved vibronic sidebands, than do related complexes with Ru-bpy chromophores; and the excited state lifetimes are characteristic of Ru-bpy MLCT excited states in this energy range. The emission yields of trans-[Ru(NH3)(4)(MDA)(pz)](2+) (MDA = py or pz) are less than 0.2%, and combined With the other observations, this implies that most of the excited state quenching occurs in high energy excited states whose population precedes that of the lowest energy (MLCT)-M-3 excited state The pz-bridged; bimetallic complexes have mixed valence excited states, and they absorb and emit at lower :energies than their monometallic analogues do.