Polarized reflectance spectra of kappa-phase ET2[Hg(SCN)Cl-2], ET2[Hg(SCN)(
2)Br], and (D-8-ET)(2)[Hg(SCN)(2)Br] single crystals are measured in the ra
nge from 600 to 40000 cm(-1). The Hubbard model for orthogonal dimers is em
ployed for interpretation of the observed charge-transfer bands and vibrati
onal peaks resulting from electron-molecular vibration coupling.