Mon, May 23 4:00pm to 7:00pm
2033 Young Hall
Speaker Prof. Sharon Glotzer
Hosted by
Dept. of Chemistry and Biochemistry and California NanoSystems Institute, UCLA

"Entropy, Information, and Alchemy of Colloids and Nanoparticles"

Abstract: For the early alchemists, the transmutation of elements held the key to new materials. Today, colloidal “elements” — that is, nanometer to micron sized particles — that can be decorated and shaped in an infinity of ways are being used to thermodynamically assemble ordered structures that would astonish the ancient alchemists in their geometric complexity and diversity. Using computer simulation methods built upon the theoretical framework of equilibrium statistical mechanics, we model and simulate these colloidal elements and the interactions among them to predict stable and metastable phases, including crystals, liquid crystals, quasicrystals, and even crystals with ultra large unit cells. Many of these structures are, remarkably, achievable via entropy maximization in the absence of other forces, using only shape. By studying families of colloidal elements and their packings and assemblies, we deduce key elemental requirements for certain classes of structures.  Recently, we have shown how extended thermodynamic ensembles may be derived and implemented in computer simulations to perform “digital alchemy,” whereby fast algorithms quickly discover optimal colloidal elements for given target structures. Through digital alchemy, we learn which elemental attributes are most important for thermodynamic stability and assembly propensity, and how information is encoded locally to produce order globally.


Location: 2033 Young Hall

Time: 4:00 PM


Location: 3037 Young Hall

Time: 5:15 PM