Louisa Brown '09 (South Wales, NY) is spending her second summer working with Professor of Chemistry Karen Brewer. Brown is a STEP/Dreyfus recipient returning for her second year of lab work. She is involved in one of Brewer's lab projects with rare earth metals, in which she chelates rare earth metals with different diketones to compare the resulting fluorescence.
Rare earth metals fluoresce when exposed to the air, but eventually stop glowing because they react with the water in the atmosphere. This fluorescence makes rare earth metals a good candidate for laser technology, but their performance is limited and unstable. The idea would be, of course, to figure out some way to make them fluoresce both longer and brighter, which is what Brown is attempting to do.
In the lab, she tries to attach organic molecules called diketones to rare earth metals. The appeal of diketones is that they could potentially protect the rare earth from quenching by water. If the chelate synthesis is successful, the resulting compound forms a powder which can then be heated into a glass. Brown can compare the fluorescence spectrum that results from the glass to the spectrum shown by the powder before it was made into glass. The biggest challenge, Brown explains, is finding the right solvent for the powders. She has been using the solvent dimethyl sulfoxide (DMSO), but is concerned that the solvent may have dismantled the chelate compounds.
Brown worked on this project last summer as well, and she says she feels that this summer she has been very productive. "I'm really pleased," she says of her progress. She hopes to be at "a stopping point" by the end of the summer, although she expresses interest in returning to rare earth metals and fluorescence at a later date, when she has made a more advanced study of physics.
Brown, a rising sophomore, is a member of the intramural fencing team and is considering applying for a junior year abroad in Paris.
-- by Lisbeth Redfield
