Molecular and spectroscopic properties of chloride and thiocyanate hydridecarbonyl ruthenium(II) complexes with pyridine derivative ligands

► The crystal and electronic structures of four ruthenium(II) hydrido-carbonyl complexes have been determined. ► The electronic spectra of the complexes were calculated with use of the TD-DFT method and associated with the structure of the molecular orbitals of the complexes. ► The emission properties of the complexes have been examined. The thiocyanate derivative of the complex with the 2,2′-dipyridylamine ligand exhibits very intense luminescence compared with the chloride analog. The emission intensification was associated with matching the energy of the d ruthenium orbitals and the π-orbitals of NCS-.