The compounds PtCl(Et 2 S)(thpy), Pt(Et 2 S)I(thpy), and Pt(phpz)(thpy), where thpy denotes the 2-(2 -thienyl)pyridine anion and phpz the (1-phenyl)pyrazole anion, were investigated by optical spectroscopy. Solid state emission down to T = 1.3 K and low temperature luminescence of the Shpol'skii system Pt(phpz)(thpy)/n-octane are presented. Thereby, electronic origins and vibronic structure with high resolution were detected. These essentially involve the Pt(II) coordinated thpy - ligand ([Pt(thpy)]-unit) of the heteroleptic compounds. A detailed comparison with the sharp emission lines of related compounds is performed. The characteristics of zero field splitting and vibronic structure give new criteria for the assignment of the lowest excited states. Weak exchange coupling within the ML π-system, including phase coupling of vibronic interactions, is proposed to explain the spectroscopic peculiarities in connection with the specific coordination properties of the title compounds.