In 1962, when Jacox joined what would become the National Institute of Standards and Technology, "there was a very big question mark about free radicals," she said. "There were about 10 that were known at the time." Forty-two years later, a reference book she authored contained 3,450 of them -- hundreds of which she has either discovered or investigated herself.
Her approach is to study their spectra, unique "fingerprints" based on exciting free radicals with light energy. Of particular interest are infrared spectra, which convey information about not only how the atoms that make up a free radical are arranged but also how they bond to one another.
Today, free radicals are commonly associated with molecules that can destroy Earth's ozone layer or damage DNA. But they are also responsible for driving reactions that otherwise wouldn't take place.
"A match flame is full of small free radicals -- without them, the flame would go away," Jacox pointed out. "And the fluoride-containing molecules used in etching microcircuits -- a lot of the chemistry of those reactions involve small free radicals I've studied. Understanding breeds control."
When asked how she originally became interested in science, particularly chemistry, Jacox said, "I was just wired to love the natural world. It started as a love for creepy crawly things as a tiny child, and then when I was only 7 years old my father gave me a child's guide to astronomy. I just ate that up."
Later, in high school, an older student who shared her bus befriended her. "She wanted to become a chemist -- this was the mid-1940s --
Contact: Allison Byrum
American Chemical Society