ConMol

CONMOL - Tailor-made Conjugated Molecular Materials via Intra- and Intermolecular Control
Financed by the Spanish ‘Ministerio de Economia y Competitividad’ 01/2012-12/2014 (MEC, Project ConMol, Grant No. CTQ2011-27317)


During the last decades, conjugated organic materials have found immense interest as active layers in (opto)electronic applications such as organic LEDs, solar cells, lasers, field effect transistors, sensors or optical memory devices. However, rational design of the materials with defined electronic, optical and photophysical properties in the solid state suffers from the complex interplay of intra- and intermolecular contributions, and from disorder usually found in polymeric samples.
The CONMOL project therefore explored structurally and electronically well-defined oligomeric materials forming single crystals with known crystal structure, so that all intra- and intermolecular structural factors are fully understood. The project was based on an extensive library of compounds (provided by our collaborators in materials science from Spain and abroad) with the same principle backbone, but systematically varying nature, position and number of electronically and/or sterically active substituents, which allowed realizing all possible intermolecular arrangements. In fact, the packing turned out to have a great impact on the resulting electronic and optical properties. Detailed experimental photophysical studies, hand-in-hand with advanced structural characterization and quantum-chemical calculations provided an in-depth understanding of how intra- and intermolecular contributions, as well as morphological factors control solid state exciton formation and their fate; in particular strength, color and spectral shapes of spontaneous and stimulated light emission.
Our detailed insight into solid state structure-property relationships of organic conjugated compounds turned out to be an important step towards the rational design of supramolecular assemblies through specific secondary forces for bright emissive, color-tunable organic crystals, showing superior lasing and/or charge transport properties. In particular, it opened the path towards the design of complex bi-chromophoric multi-stimuli responsive systems by specific control of packing modes, forming the next generation of optoelectronic devices.
Results of the CONMOL research were up to now published in more than twenty original research papers including six review & feature articles, inter alia in high impact journals such as Angew. Chem., J. Am. Chem. Soc., Adv. Mater. and Acc. Chem. Res., with already 370 citations (04/2015; project h-index = 9). Numerous (invited) talks of the project researchers at international conferences and research institutes further enhanced the visibility of CONMOL, stimulating new collaborations and inter-/national projects.
Researchers involved:
Dr. Johannes Gierschner (PI, PL spectroscopy, modelling)
Dr. Larry Lüer (fs pump-probe spectroscopy)
Dr. Begoña Milián Medina (quantum-chemistry)
Dr. Arantxa Aguirre (project Postdoc)
Junqing Shi (project PhD student)
Dr. Shinto Varghese (associated researcher)
Dr. Santanu Bhattacharyya (associated researcher)
Inhouse collaborations (IMDEA Nanoscience)
Dr. Reinhold Wannemacher (Lasing and lowT studies)
Dr. Santiago Casado (AFM studies)
Dr. Enrico Gnecco (Friction Force AFM)
Dr. Feng Luo (Thin film epitaxial growth)
External Collaborations
Prof. Dr. Soo Young Park, Seoul National University (Materials)
Prof. Dr. Gianluca Farinola, Univ. Bari (Materials)
Prof. Dr. Roland Resel, Univ. Graz (SXRD)
Prof. Dr. Roland Fischer, Univ. Graz (single crystal x-ray)
Prof. Dr. María Díaz, Univ. Alicante (SRRS)
Prof. Dr. Carlos Pina, Univ. Complutense Madrid (Friction Force AFM)
Prof. Dr. Blanca Ros & Dr. Raquel Giménez, Univ. Zaragoza (Bent-core Liquid Crystals)
Industry
SYNCHIMIA


Publications:
High Contrast Red-Green-Blue Tricolor Fluorescence Switching in Bicomponent Molecular Film
H.-J. Kim, D. R. Whang, J. Gierschner, C. H. Lee, S. Y. Park, Angew. Chem. Int. Ed. 54 (2015) 4330-4333.

A Distyrylbenzene Based Highly Efficient Deep Red/Near-Infrared Emitting Organic Solid
M. A. Kim, D. R. Whang, J. Gierschner, S. Y. Park, J. Mater. Chem. C 3 (2015) 231-234.

Molecular Resolution Friction Microscopy of Cu Phthalocyanine Thin Films on Dolomite (104) in Water
P. Nita, C. Pimentel, F. Luo, B. Milián-Medina, J. Gierschner, C. M. Pina, E. Gnecco, Nansocale 6 (2014) 8334-8339.

Orthogonal Resonator Modes and Low Lasing Threshold in Highly Emissive Distyrylbenzene-Based Molecular Crystals
S. Varghese, S-J. Yoon, S. Casado, R. Fischer, R. Wannemacher, S. Y. Park, J. Gierschner, Adv. Opt. Mater. 2 (2014) 542–548.

Rationally Designed Molecular D–A–D Triad for Piezochromic and Acidochromic Fluorescence On–Off Switching
M. S. Kwon, J. Gierschner, J. Seo, S. Y. Park, J. Mat. Chem. C 2 (2014) 2552-2557.

Computational Engineering of Low Bandgap Copolymers
M. Wykes, B. Milián Medina, J. Gierschner, Front. Chem. 1 (2013) 35.

Luminescent Distyrylbenzenes: Tailoring Molecular Structure and Crystalline Morphology
J. Gierschner, S. Y. Park, J. Mater. Chem. C 1 (2013) 5818–5832.

see also... Hot Papers J. Mater. Chem. 2013, and ChemInform
Highly Emissive H-Aggregates or Aggregation-Induced Emission Quenching? The Photophysics of All-Trans Para-Distyrylbenzene
J. Gierschner, L. Lüer, B. Milián-Medina, D. Oelkrug, H.-J. Egelhaaf, J. Phys. Chem. Lett. 4 (2013) 2686-2697.

Watch the video a/o take a look at the LifeSlides, and read the Editor's Comment
Stimulated Emission Properties of Sterically Modified Distyrylbenzene-Based H-Aggregate Single Crystals
S. Varghese, S. K. Park, S. Casado, R. Fischer, R. Resel, B. Milián-Medina, R. Wannemacher, S. Y. Park, J. Gierschner, J. Phys. Chem. Lett. 4 (2013) 1597–1602.

Tailor-made Highly Luminescent and Ambipolar Transporting Organic Mixed Stacked Charge-Transfer Crystals: an Isometric Donor-Acceptor Approach
S. K. Park, S. Varghese, J. H. Kim, S.-J. Yoon, O. K. Kwon, B.-K. An, J. Gierschner, S. Y. Park, J. Am. Chem. Soc. 135 (2013) 4757-4764.

Color-Tuned, Highly Emissive Dicyanodistyrylbenzene Single Crystals: Manipulating Intermolecular Stacking Interactions for Spontaneous and Stimulated Emission Characteristics
S.-J. Yoon, S. Varghese, S. K. Park, R. Wannemacher, J. Gierschner, S. Y. Park, Adv. Opt. Mater. 1 (2013) 232-237.

Correlation Effects in the Optical Spectra of Porphyrin Oligomer Chains: Exciton Confinement and Length Dependence
C. Hogan, M. Palummo, J. Gierschner, A. Rubio, J. Chem. Phys. 138 (2013) 024312.

Fluoro-Functionalization of Vinylene Units in a Polyarylenevinylene for Polymer Solar Cells: Impact of Fluorination on Morphological and Optical Properties and on Photovoltaic Performances
A. Cardone, C. Martinelli, M. Losurdo, E. Dilonardo, G. Bruno, G. Scavia, S. Destri, P. Cosma, L. Salamandra, A. Reale, A. Di Carlo, A. Aguirre, B. Milián-Medina, J. Gierschner, G. M. Farinola, J. Mater. Chem. A 1 (2013) 715-727.

Stimulated Resonance Raman Scattering and Lasing Oscillation in Highly Emissive Distyrylbenzene Based Molecular Crystals
S. Varghese, S.-J. Yoon, E. M. Calzado, S. Casado, P. G. Boj, M. A. Díaz-García, R. Resel, R. Fischer, B. Milián-Medina, R. Wannemacher, S. Y. Park, J. Gierschner, Adv. Mater. 24 (2012) 6473-6478.

Unique Piezochromic Fluorescence Behavior of Dicyanodistyrylbenzene Based Donor–Acceptor–Donor Triad: Mechanically Controlled Photo-induced Electron Transfer (eT) in Molecular Assemblies
M. S. Kwon, J. Gierschner, S.-J. Yoon, S. Y. Park, Adv. Mater. 24 (2012) 5487–5492.



Directional Exciton Transport in Supramolecular Nanostructured Assemblies
J. Gierschner, Phys. Chem. Chem. Phys. 14 (2012) 13146-13153.

p-Conjugated Cyanostilbene Derivatives: A Unique Self-Assembly Motif for Molecular Nanostructures with Enhanced Emission and Transport
B.-K. An, J. Gierschner, S. Y. Park, Acc. Chem. Res. 45 (2012) 544-554.

Computational Design of Low Singlet-Triplet Gap All-Organic Molecules for OLED application
B. Milián-Medina, J. Gierschner, Org. El. 13 (2012) 895-911.