(2020) Order From Disorder: Molecular Packing in Glasses

Using physical vapor deposition, researchers produced glassy films that are smooth and uniform, but which also have the molecules aligned with one another and organized in layers. This added structure could make the glass more efficient for conductors and expand the range of materials that can be used in future organic electronics.  The colorful images in the figure show measurements using synchrotron x-rays that contrast the disordered starting material and the ordered glass.

(2019) Mechanical Properties of Structure-TunableVapor-Deposited TPD Glass

Creating glassy thin films of organic molecules at different temperatures changes both their stability in the glassy state – their density, and how hard they are to melt – and it changes how the molecules in the films are arranged – whether they tend to lie down flat on the surface or stand straight up. Wisconsin MRSEC researchers have shown that these changes in stability and average molecular orientation also change the mechanical properties of the film, including how stiff it is and how hard it is.