Functional Organic Solid State Materials Derived from Designer Host Frameworks DMR-0305278 Michael D. Ward, University of Minnesota. Hydrogen-bonded frameworks trap laser dyes.
Functional Organic Solid State Materials Derived from Designer Host Frameworks
Michael D. Ward, University of Minnesota
Figure 1. Solid state structure of the inclusion compound based on the guanidinium biphenyldisulfonate host framework and coumarin 102 guest molecules. Coumarin 102 , which is a commercially available laser dye, packs in the voids of the polar orthorhombic host framework. This framework and others also incorporate pyrene and perylene guest molecules, and the aggregation state of the guests (e.g., H-aggregates vs. J-aggregates) can be regulated through the choice of the pillar-guest combination.
Figure 2. (A) Selectivity profiles of pairwise competition for inclusion of three of the ten dimethylnaphthalene (DMN) isomers by the “chevron” pillar o-diphenylbenzenedisulfonate, for which both sulfonate groups anchor to the same GS sheet to produce bilayer-like architecture with interdigitation of the o-DPB groups. The profiles reveal that inclusion of 1,5-DMN is highly preferred, opposite to behavior observed earlier for other host systems (X = mol fraction in solution; Y = mol fraction included). (B) The crystal structure of the 1,5-DMN inclusion compound.
published her first paper (Crystal Growth & Design, 2005, 5, 995)
International and other Activities
NOTES Designer Host Frameworks
Figure 1. We have found that the hydrogen-bonded frameworks generated from guanidinium cations and a variety of organomonosulfonates and organodisulfonates forms hundreds of inclusion compounds with retention of the hydrogen bond connectivity of the guanidinium-sulfonate sheet. The remarkable persistence of the GS sheet, which is unique in the organic solid state, is attributable to the strength of the charge-assisted hydrogen bonds and the pliable nature of the sheet, which permits “puckering” that accommodates the packing of the organic constituents. Consequently, this system has emerged as a benchmark for organic crystal design, and it continues to surprise while serving as a platform for advancing our understanding of molecular organization in the solid state. Previously we demonstrated the de novo design of polar inclusion compounds with second harmonic generation activity that could be regulated by the choice of guest. Here, we depict a recently discovered inclusion compound that contains the laser dye coumarin 102. Because the guest organization can be controlled by the choice of framework, the inclusion of laser dyes, as well as pyrene and perylene, suggests a new generation of materials with interesting, and possible useful, optical properties.