SPECTRAL STUDIES OF ISOSTRUCTURAL ORGANIC METALS (BEDT-TTF)3(HSO4)2 AND [NI(DDDT)2]3(HSO4)2

The polarized reflectance spectra of (BEDT-TTF)3(HSO4)2 and [Ni(dddt)2 ]3(HSO4)2 crystals are measured in the IR region (660 to 5200 cm-1) at room temperature. Moreover, the powder absorption spectra in the freq uency range 400 to 40000 cm-1 are reported. Differences between charge transfer bands of both compounds are found. In [Ni(dddt)2]3(HSO4)2 th e strong coupling of electrons with vibrations of C=C ring bonds is ob served. The phase transition in (BEDT-TTF)3(HSO4)2 at the temperature T = 130 K influences the IR powder absorption spectra, especially with in the range of C=C vibrations.