Photoconversion of lutetium diphthalocyanine and interpretation of its electronic absorption spectra
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Abstract
When frozen solutions of lutetium diphthalocyanine (LuPC2) in a mixture of methylene chloride with trichloroethylene are irradiated by UV light, monocations of LuPC2 form. The photoreaction is slowed and ceases in an early stage apparently due to the reversibility of the photoconversion in this system. The reduced form of LuPC2 (its monoanions) are completely converted into the neutral form of LuPC2 during irradiation. When this photoconversion is carried out in a frozen solution, the electronic absorption bands in the spectrum of the LuPC2 formed are displaced in comparison to the bands of the original substance under the same conditions, posibly due to the difference between the structures of the solvation shells. An interpretation of the electronic absorption spectrum of LuPC2 in the 300–1600-nm region has been given on the basis of the scheme of the molecular orbitals of sandwich phthalocyanine dimer with one π-electronic vacancy.
Keywords
Methylene Chloride Absorption Spectrum Absorption Band Methylene ChloridePreview
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