The theoretical calculations, however, could not account for the apparent offset
seen in Fig. 21b. It has been speculated that this off-set might be traced back to a
coherent coupling mechanism contributing to the optical line width [9]. Finally,
theoretical results for 1 in PMMA have yielded an excellent agreement between the
Fo ¨rster screening factor 1/n
4 and a screening factor obtained by considering a cavity
enclosing the dyad inside the PMMA dielectric environment [132].
Acknowledgement The contributions of our co-workers Burkhard Fu ¨ckel, Long Chen, Gregor
Diezemann, Gerald Hinze, Ting Ren, Daniel Wenzlik, Mara Werwie and Xiangxing Xu are
gratefully acknowledged.
References
1. Hu ¨bner CG, Ksenofontov V, Nolde F, Mu ¨llen K, Basche ´ T (2004) Three-dimensional
orientational colocalization of individual donor–acceptor pairs. J Chem Phys 120:10867
2. Metivier R, Nolde F, Mu ¨llen K, Basche ´ T (2007) Electronic excitation energy transfer
between two single molecules embedded in a polymer host. Phys Rev Lett 98:047802
3. Fu ¨ckel B, Ko ¨hn A, Harding ME, Diezemann G, Hinze G, Basche ´ T, Gauss J (2008)
Theoretical investigation of electronic excitation energy transfer in bichromophoric assemblies. J Chem Phys 128:074505
4. Fu ¨ckel B, Hinze G, Nolde F, Mu ¨llen K, Basche ´ T (2009) Control of the electronic excitation
energy transfer pathway between two single fluorophores by dual pulse excitation. Phys Rev
Lett 103:103003
5. Tour JM (1994) Soluble oligo- and polyphenylenes. Adv Mater 6:190
6. Wicklein A, Lang A, Muth M, Thelakkat M (2009) Swallow-tail substituted liquid crystalline
perylene bisimides: synthesis and thermotropic properties. J Am Chem Soc 131:14442
7. Nolde F, Qu J, Kohl C, Pschirer NG, Reuther E, Mu ¨llen K (2005) Synthesis and modification
of terrylenediimides as high-performance fluorescent dyes. Chem Eur J 11:3959
8. Hinze G, Haase M, Nolde F, Mu ¨llen K, Basche ´ T (2005) Time-resolved measurements of
intramolecular energy transfer in single donor/acceptor dyads. J Phys Chem A 109:6725
Fig. 24 Coupling of a p-terphenyl to the PDI chromophore (left). Shown are the isosurfaces of
(a) the transition density and (b) the difference density. The calculations were performed with the
CC2 method and a SVP basis set. Reproduced with permission from [3]. Copyright 2008 American
Institute of Physics
Optical Properties of Assemblies of Molecules and Nanoparticles
107
seen in Fig. 21b. It has been speculated that this off-set might be traced back to a
coherent coupling mechanism contributing to the optical line width [9]. Finally,
theoretical results for 1 in PMMA have yielded an excellent agreement between the
Fo ¨rster screening factor 1/n
4 and a screening factor obtained by considering a cavity
enclosing the dyad inside the PMMA dielectric environment [132].
Acknowledgement The contributions of our co-workers Burkhard Fu ¨ckel, Long Chen, Gregor
Diezemann, Gerald Hinze, Ting Ren, Daniel Wenzlik, Mara Werwie and Xiangxing Xu are
gratefully acknowledged.
References
1. Hu ¨bner CG, Ksenofontov V, Nolde F, Mu ¨llen K, Basche ´ T (2004) Three-dimensional
orientational colocalization of individual donor–acceptor pairs. J Chem Phys 120:10867
2. Metivier R, Nolde F, Mu ¨llen K, Basche ´ T (2007) Electronic excitation energy transfer
between two single molecules embedded in a polymer host. Phys Rev Lett 98:047802
3. Fu ¨ckel B, Ko ¨hn A, Harding ME, Diezemann G, Hinze G, Basche ´ T, Gauss J (2008)
Theoretical investigation of electronic excitation energy transfer in bichromophoric assemblies. J Chem Phys 128:074505
4. Fu ¨ckel B, Hinze G, Nolde F, Mu ¨llen K, Basche ´ T (2009) Control of the electronic excitation
energy transfer pathway between two single fluorophores by dual pulse excitation. Phys Rev
Lett 103:103003
5. Tour JM (1994) Soluble oligo- and polyphenylenes. Adv Mater 6:190
6. Wicklein A, Lang A, Muth M, Thelakkat M (2009) Swallow-tail substituted liquid crystalline
perylene bisimides: synthesis and thermotropic properties. J Am Chem Soc 131:14442
7. Nolde F, Qu J, Kohl C, Pschirer NG, Reuther E, Mu ¨llen K (2005) Synthesis and modification
of terrylenediimides as high-performance fluorescent dyes. Chem Eur J 11:3959
8. Hinze G, Haase M, Nolde F, Mu ¨llen K, Basche ´ T (2005) Time-resolved measurements of
intramolecular energy transfer in single donor/acceptor dyads. J Phys Chem A 109:6725
Fig. 24 Coupling of a p-terphenyl to the PDI chromophore (left). Shown are the isosurfaces of
(a) the transition density and (b) the difference density. The calculations were performed with the
CC2 method and a SVP basis set. Reproduced with permission from [3]. Copyright 2008 American
Institute of Physics
Optical Properties of Assemblies of Molecules and Nanoparticles
107