Synthesis of silicon phthalocyanine μ-oxo dimers to octamers and their dipole-dipole-type coupling observed in the absorption and MCD spectra

μ-Oxo oligomers constituting of two to eight tert-butylated silicon phthalocyanines have been synthesized and their electronic absorption and magnetic circular dichroism (MCD) spectra recorded. From the shift of the Q absorption peak and the midpoint of Q MCD peak and trough, it was concluded that the increment in long-range dipole-dipole exciton interaction decreases with an increase in the number of units and approaches saturation in hexamers.