Cover Profile
DOI: 10.1002/cphc.201500225
Polymorphism in New Thienothiophene–Thiazolothiazole Organic Semiconductors
McGill University, Chemistry Department Montr¦al, QC, H3A 0B8, Canada E-mail: [email protected] Homepage: http://perepichka-group.mcgill.ca/ Julia A. Schneider
Dr. Hayden T. Black
Dr. Hua-Ping Lin
Prof. Dmitrii Perepichka
The front cover artwork is provided by J. A. Schneider from D. Perepichka’s group (McGill University). The image shows two packing motifs of the same organic semiconductor, which either hinder or facilitate charge transport. In the foreground the crystal polymorphs and a single crystal field-effect transistor are pictured. Read the full text of the article at 10.1002/ cphc.201500066.
What aspects of this project do you find most exciting? Our project started with the synthesis of p-conjugated molecules designed for the study of sulfur and nitrogen heteroatoms. When we discovered two crystalline polymorphs of our molecules, we were able to analyze the role of intermolecular ordering, independently from intramolecular structural and electronic effects. It was exciting to see how changes in the crystal structure yielded polymorphs with differing appearances, fluorescence properties, and most importantly, charge mobilities.
those described here, other current topics include synthesis of two-dimensional polymers, molecular reactivity and self-assembly on surfaces, and supramolecular control of active semiconductors through complementary hydrogen bonding. Our applications range from field-effect transistors and radiation detectors to photovoltaic devices and batteries.
Acknowledgments This work was funded by NSERC. J.A.S. and H.P.L. acknowledge support through Vanier and FRQS fellowships, respectively.
Did serendipity play a part in this work?
In this work crystals were grown by physical vapor transport in a tube furnace, of which our laboratory has two. Only one of these furnaces provides the specific temperature gradient required to separate the two polymorphic forms we reported. If we had only used one of the furnaces we might have missed one of the most interesting aspects of these molecules!
What is in your opinion an upcoming research theme likely to become one of the ’hot topics’ in the near future?
As the morphology of organic materials plays a dominant role in their device performance, controlling this “supramolecular structure” is paramount to further progress in the field. We believe this will be achieved through a combination of experimental techniques and calculations. As calculations improve packing motifs can be predicted, giving rise to the computational screening of charge and exciton dynamics in new materials. Simultaneously, new tools for characterizing supramolecular structures, particularly at the nanoscale, and new methods of tailoring self-assembly properties will allow for the rational design of more complex electronic materials, such as bulk heterojunction films.
What other topics are you working on at the moment?
Our group works on a variety of topics relevant to organic electronics and supramolecular chemistry. One of our main goals is engineering new electronic properties in organic materials. Besides designing molecular semiconductors such as
ChemPhysChem 2015, 16, 1102
1102
Ó 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
DOI: 10.1002/cphc.201500225
Polymorphism in New Thienothiophene–Thiazolothiazole Organic Semiconductors
McGill University, Chemistry Department Montr¦al, QC, H3A 0B8, Canada E-mail: [email protected] Homepage: http://perepichka-group.mcgill.ca/ Julia A. Schneider
Dr. Hayden T. Black
Dr. Hua-Ping Lin
Prof. Dmitrii Perepichka
The front cover artwork is provided by J. A. Schneider from D. Perepichka’s group (McGill University). The image shows two packing motifs of the same organic semiconductor, which either hinder or facilitate charge transport. In the foreground the crystal polymorphs and a single crystal field-effect transistor are pictured. Read the full text of the article at 10.1002/ cphc.201500066.
What aspects of this project do you find most exciting? Our project started with the synthesis of p-conjugated molecules designed for the study of sulfur and nitrogen heteroatoms. When we discovered two crystalline polymorphs of our molecules, we were able to analyze the role of intermolecular ordering, independently from intramolecular structural and electronic effects. It was exciting to see how changes in the crystal structure yielded polymorphs with differing appearances, fluorescence properties, and most importantly, charge mobilities.
those described here, other current topics include synthesis of two-dimensional polymers, molecular reactivity and self-assembly on surfaces, and supramolecular control of active semiconductors through complementary hydrogen bonding. Our applications range from field-effect transistors and radiation detectors to photovoltaic devices and batteries.
Acknowledgments This work was funded by NSERC. J.A.S. and H.P.L. acknowledge support through Vanier and FRQS fellowships, respectively.
Did serendipity play a part in this work?
In this work crystals were grown by physical vapor transport in a tube furnace, of which our laboratory has two. Only one of these furnaces provides the specific temperature gradient required to separate the two polymorphic forms we reported. If we had only used one of the furnaces we might have missed one of the most interesting aspects of these molecules!
What is in your opinion an upcoming research theme likely to become one of the ’hot topics’ in the near future?
As the morphology of organic materials plays a dominant role in their device performance, controlling this “supramolecular structure” is paramount to further progress in the field. We believe this will be achieved through a combination of experimental techniques and calculations. As calculations improve packing motifs can be predicted, giving rise to the computational screening of charge and exciton dynamics in new materials. Simultaneously, new tools for characterizing supramolecular structures, particularly at the nanoscale, and new methods of tailoring self-assembly properties will allow for the rational design of more complex electronic materials, such as bulk heterojunction films.
What other topics are you working on at the moment?
Our group works on a variety of topics relevant to organic electronics and supramolecular chemistry. One of our main goals is engineering new electronic properties in organic materials. Besides designing molecular semiconductors such as
ChemPhysChem 2015, 16, 1102
1102
Ó 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
