“Super Cool” Research at SJU
Chemistry professor awarded NSF grant for research on glass-forming liquids
Tuesday, October 9, 2012
by Olivia D'Atri '14
PHILADELPHIA (Oct. 8, 2012) - John Berberian, Ph. D., professor of chemistry, has received a $302,228 Research in Undergraduate Institutions (RUI) grant from the National Science Foundation for his proposal, “The Study of Molecular Motion in Simple Glass-Forming Liquids.”
Berberian hopes to further understand the forces involved in the behavior of simple glass- forming materials above and near the glass transition temperature, and points to practical applications for the research.
“This work could eventually help engineers develop new and better materials with properties geared to specific uses, and will also give insight into the macroscopic properties of these materials,” Berberian says.
“Glass” refers to both the more familiar window glass and to many other substances that share its properties, especially the way in which molecules are arranged, according to Berberian. The glass transition temperature refers to the temperature at which these substances change from being more like a liquid to being more like a solid.
“Simple glass-forming liquids ‘super-cool’ – that is, when the liquid is cooled rapidly, the molecules lose their energy too fast to form a solid, and therefore remain a liquid even though the temperature is below their freezing point,” Berberian says.
Instead of crystallizing, like water turning into ice, the molecules stay in a state of non-equilibrium due to a lack of energy from rapid cooling. These super-cooled liquids will eventually crystallize, but, depending on their temperature, it may take a day, weeks or even years for this to occur.
“We are trying to discover what the fundamental molecular structure is at this temperature, and what the molecules are doing at this point,” Berberian says.
About half of the grant will fund new equipment, specifically thermal analysis instrumentation, which will allow Berberian to use heat capacity measurements to examine internal modes of energy storage. In addition, other electrical instrumentation will be used for dielectric spectroscopy measurements that examine the energy of molecular rotation in the super-cooled liquid. The thermal analysis instrument – a Modulated Differential Scanning Calorimeter – will support other research and teaching activities in the Department of Chemistry.
As an RUI grant, the funding will have the most vital impact on the students working in Berberian’s research group who will participate in the University’s Summer Scholars Program (SSP), which gives students the opportunity to work closely and collaboratively with faculty mentors on research projects. Scholars are required to write about their work and present it publicly later in the school year. SSP participants receive a stipend of $3,200, and have the option of on-campus housing at a reduced cost