A series of ruthenium tris(beta-diketonate), was investigated using electrochemistry, UV-Vis spectroscopy, 1H and 13C NMR and FAB mass spectroscopy. Several new mononuclear mixed-ligand ruthenium(III) complexes including - dibenzoylmethanate ion (dbm); [Ru(dbm)3] 1 - one or two acetylacetonate ion (2,4-pentanedionate, acac-); [Ru(dbm)2(acac)] 2, [Ru(dbm)(acac)2] 3 - acetonitrile ligand; [Ru(dbm)2(CH3CN)2][CF3SO3] 4 - or functionalized acetylacetonate ion; [Ru(dbm)2(acac-I)] 5 (acac-I = 3-iodo-2,4-pentanedionate ion), [Ru(dbm)2(acac-Br)] 6 (acac-Br = 3-bromo-2,4-pentanedionate ion) were prepared. In addition, X-Ray structures for complexes 1, 2, 3, 4 and 6 were determined. Scanning tunneling microscopy measurement at liquid He temperature and in ultra high vacuum (UHV-STM) of complex 1 on Ag(111) surface was conducted. This indicates that the complex can be successfully evaporated and observed after adsorption on a metallic substrate. Analysis of the STM images, supported by adsorption and STM image calculations demonstrates that the molecules exist in two stable forms when adsorbed on the surface.