Authors: H.-L. Wang, Z. Tang, Y. Gao, R.J. Magyar, S. Tretiak, A.P. Shreve
Affilation: Los Alamos National Laboratory, United States
Pages: 754 - 757
Keywords: Langmuir, self-assembly, noncavalent interaction, azobenzene
We strive to design syntheses of a series of amphiphilic molecular building blocks that can self-assembled at the air-water interface to form 2D and 3D nanostructures with specific opto-electronic properties. Compression of these molecular building blocks – azobenezene derivatives with tunable dipole-dipole interactions– using Langmuir-Blodgett method gives rise to monolayer thin films with different packing density and electronic coupling between chromophores. Depends on the dipole-dipole interactions, we observe a transition of thin film from amorphous to ordered structures and this transition is exhibited in their optical spectroscopy. Furthermore, we use a series of spectroscopy tools such as neutron and X-ray reflectometery to probe the nanoassembly structures at the molecular level. We also use simulation method to help determine how molecules come together at the air-water interface. Our results demonstrate that the interplay between dipole-dipole and ?-? interactions dominate the formation of amorphous and ordered thin films and their associated properties. Based on our understanding, we expect to achieve synthesis of a wide range of 2D and 3D functional nanoassemblies that are previous inaccessible.