Random dipole model for optical excitations in extended dendrimers
نویسنده
چکیده
A phenomenological random dipole model is proposed in order to characterize optical excitations in extended dendrimers. A transition dipole moment is assigned at each phenyl rings and a nearest neighbor hopping integral which obeys the Gaussian distribution is considered between the dipoles. The decreasing optical excitation energy with respect to the dendrimer size indicates the presence of exciton funnels along the backbone of the dendrimers. Therefore, the extended dendrimers can work as artificial fractal antenna systems which capture energy of light. PACS numbers: 36.20.Kd, 71.35.Cc, 31.50.+w, 78.66.Qn ∗E-mail address: [email protected]; URL: http://www.etl.go.jp/ ̃harigaya/
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