News and dates
04.05.12 - Light and Matter
Chemists and physicists at the Center for Nanosystems Chemistry have initiated a new collaboration at the University of Wuerzburg. The aim of their work is to design and produce novel materials with tailored properties for efficient interaction with...
16.04.12 - Siegfried Hünig Lecture 2012 will be given by Nobel Laureate
Prof. Jean-Marie Lehn (Université de Strasbourg) will give the Siegfried Hünig Lecture 2012 on May, 7th.
29.03.12 - Center for Nanosystems Chemistry Becomes Key Lab for Supramolecular Photocatalysis and Photovoltaics
"Solar Technologies Go Hybrid" is the title of a new research initiative funded by the State of Bavaria. The Center of Nanosystems Chemistry at the University of Würzburg will receive almost a quarter of the total funding sum.
27.03.12 - PhD Defence
On March 23, 2012 Antti Ojala from Finland successfully defended his PhD thesis on "Merocyanine Dyes as Donor Materials in Vacuum-Deposited Organic Solar Cells: Insights into Structure-Property-Performance Relationships". Antti Ojala...
16.02.12 - PhD Defence
On February 15, 2012, Ulrich Mayerhöffer successfully defended his PhD thesis with distinction on "Synthese, Eigenschaften und funktionale Anwendung von NIR absorbierenden Squarainen". We congratulate Ulrich and wish him all the best...
23.12.11 - Christmas Party 2011
The groups of the core center had a very enjoyable annual Christmas party that included home made Indian food expertly paired with local Franconian wines. Real fun came during the traditional "Wichteln" game. However, the highlight of ...
Featured Recent Publications
>Bright Near-Infrared Fluorophores Based on Squaraines by Unexpected Halogen Effects
U. Mayerhöffer, B. Fimmel, F. Würthner
Angew. Chem. 2012, 124, 168–171; Angew. Chem. Int. Ed. 2012, 51, 164–167. DOI: 10.1002/anie.201107176
An unexpected halogen effect afforded novel squaraine-based bright near-infrared (NIR) fluorophores with nearly total transparency in the visible region and bright emission in the NIR region beyond 900 nm (see picture).

>Efficient Solution Bulk Heterojunction Solar Cells by Antiparallel Supramolecular Arrangement of Dipolar Donor-Acceptor Dyes
H. Bürckstümmer, E. V. Tulyakova, M. Deppisch, M. R. Lenze, N. M. Kronenberg, M. Gsänger, M. Stolte, K. Meerholz, F. Würthner
Angew. Chem. 2011, 123, 11832–11836; Angew. Chem. Int. Ed. 2011, 50, 11628–11632. DOI: 10.1002/anie.201105133
Donor-acceptor dyes with aminothiophene donor show ideal absorption, redox, and packing feature in organic photovoltaics. With blend of HB366:PC71BM, highly efficient solar cells were achieved with a VOC of 1.0 V, a JSC of 10.2 mA cm−2, and a power conversion efficiency of 4.5%.
>Foldamer with a spiral perylene bisimide staircase aggregate structure
V. Dehm, M. Büchner, J. Seibt, V. Engel, F. Würthner
Chem. Sci. 2011, 2, 2094–2100. DOI: 10.1039/c1sc00435b
A molecular staircase was constructed by a new foldamer concept based on intramolecular π–π-interactions of perylene bisimide dyes.

>Self-Sorting Phenomena in Complex Supramolecular Systems
M. M. Safont-Sempere, G. Fernández, F. Würthner
Chem. Rev. 2011, 111, 5784–5814. DOI: 10.1021/cr100357h
In this review, we will discuss the external variables and intrinsic factors (molecular codes) that influence the recognition or discrimination of supramolecularly interacting chemical species in solution. The comprehension of this “molecular programming” in artificial systems will define the variables that control self-sorting processes, and may ultimately contribute to a better understanding of the self-assembly pathways in natural systems.

>Impact of Molecular Flexibility on Binding Strength and Self-Sorting of Chiral π-Surfaces
M. M. Safont-Sempere, P. Osswald, M. Stolte, M. Grüne, M. Renz, M. Kaupp, K. Radacki, H. Braunschweig, F. Würthner
J. Am. Chem. Soc. 2011, 133, 9580–9591. DOI: 10.1021/ja202696d
In this work, we have explored for the first time the influence of conformational flexibility of π-core on chiral self-sorting properties of perylene bisimides (PBIs) that are currently one of the most prominent classes of functional dyes.
>Synthesis and Characterization of Optical and Redox Properties of Bithiophene-Functionalized Diketopyrrolopyrrole Chromophores
H. Bürckstümmer, A. Weissenstein, D. Bialas, F. Würthner
J. Org. Chem. 2011, 76, 2426–2432. DOI: 10.1021/jo2003117
>J-Aggregates: From Serendipitous Discovery to Supramolecular Engingeering of Functional Dye Materials
F. Würthner, T. E. Kaiser, C. R. Saha-Möller
Angew. Chem. 2011, 123, 3436–3473; Angew. Chem. Int. Ed. 2011, 50, 3376–3410. DOI: 10.1002/anie.201002307
After more than 75 years since their discovery, J-aggregates are continuing to be of great interest. This Review provides an overview on J-aggregates of various classes of dyes, including cyanines, porphyrins, phthalocyanines, and perylene bisimides, with specific emphasis on supramolecular construction principles, optical properties, and perspectives for applications.
>Diketopyrrolopyrrole as a p-channel organic semiconductor for high performance OTFTs
S.-L. Suraru, U. Zschieschang, H. Klauk, F. Würthner
Chem. Commun. 2011, 47, 1767–1769. DOI: 10.1039/c0cc04395h
A new diketopyrrolopyrrole derivative 1 exhibits excellent hole mobilities of 0.7 cm2 V–1 s–1 and a current on/off ratio of 106 under ambient conditions in bottom-gate, top-contact organic thin film transistors (OTFTs) fabricated by vacuum deposition.









