Scientists at the University of Michigan have developed a new theory of bonding: specifically, about how nanoparticles bond to form crystals. There is an odd paradoxical quality to the new theory: it postulates that some bonding comes about because of entropy, the tendency of disorder to increase in the absence of expenditures of energy. How can this impulse-to-disorder be a glue for the ordered structure of nanoparticles? A proper explanation in this column is impossible, but their article, and its abstract, are available online.
The scientists have published their conclusions in Proceedings of the National Academy of Sciences. Two of the key figures in this work have explained their findings in laymen’s terms in a press release. Sharon Glotzer, the Anthony C. Lembke Department Chair of Chemical Engineering, and Thi Vo, a postdoctoral researcher in chemical engineering, answered some questions about their new theory, emphasized that the theory of “entropic bonding” is important both theoretically and practically. Not only may it help humans understand the world better, it may help with building stuff, too.
Strange New Worlds:
“If entropy is helping your system organize itself, you may not need to engineer explicit attraction between particles—for example, using DNA or other sticky molecules—with as strong an interaction as you thought. With our new theory, we can calculate the strength of those entropic bonds,” said Glotzer.