Skip to Main Content

ACS News

July 3, 2006
Volume 84, Number 27
p. 43

Noble Gas Reactivity Research Honored

International Historic Chemical Landmark marks Neil Bartlett's discovery of noble gas reactivity

Linda Raber

"As chemical educators, we visualize ourselves as open-minded scientists uninfluenced by authority, who pride ourselves on viewing our scientific beliefs not as absolute truths but as tentative hypotheses that we are prepared to modify or abandon in the light of new discoveries. However, in July 1962, while attending a conference ... my open-mindedness was put to the test—and I flunked!" recalled chemistry professor George B. Kauffman of California State University, Fresno, in an article for the Chemical Educator (Vol. 9, No. 6, published on the Web Nov. 24, 2004).

Photo By Linda Raber

Congratulations Neil and Christina Bartlett enjoy the festivities at the landmark celebration.

Kauffman continued: "Someone interrupted one of the lectures and announced that Neil Bartlett, a young (born 1932) and comparatively unknown lecturer at the University of British Columbia at Vancouver, had prepared a compound of an inert gas-xenon hexafluoroplatinate(V), XePtF6."

Forty-four years later, on May 23, Bartlett and his colleagues, friends, and students gathered in Vancouver where the American Chemical Society and the Canadian Society for Chemistry designated the work that established noble gas reactivity as an International Historic Chemical Landmark.

In his remarks to those gathered at the event, ACS Board Chair James D. Burke noted that the National Historic Chemical Landmarks Program has been active since 1993. Since then, more than 50 sites have been designated landmarks, from the first landmark—the Bakelizer—to the first synthetic plastic to nylon to the first house paint for do-it-yourselfers.

Burke presented a commemorative bronze plaque to R. Grant Ingram, dean of the faculty of science at the University of British Columbia. Also participating in the plaque presentation was David Schwass, vice president and incoming president of the Canadian Society for Chemistry. The text of the plaque reads in English and French:

"In this building in 1962 Neil Bartlett demonstrated the first reaction of a noble gas. The noble gas family of elements—helium, neon, argon, krypton, xenon, and radon—had previously been regarded as inert. By combining xenon with a platinum fluoride, Bartlett created the first noble gas compound. This reaction began the field of noble gas chemistry, which became fundamental to the scientific understanding of the chemical bond. Noble gas compounds have helped create antitumor agents and have been used in lasers."

Events of the day included a luncheon, which was attended by many of Bartlett's colleagues; a ceremony at which Bartlett donated some of his original lab notebooks to the university; and a public lecture in the evening. In addition, the university used the opportunity to officially christen its newly renovated Chemistry North building. The next day, the university also conferred the honorary doctor of science degree on Bartlett at its spring convocation.

Bartlett has clear memories of his discovery of xenon oxidation that he's happy to share. He recalls that early in 1962, while preparing a lecture, he noticed the common textbook illustration showing that the first ionization potential for the elements in any group in the periodic table falls with increasing atomic number. "Immediately, I realized that the heavier noble gases had ionization potentials like that of O2, which my graduate student Derek Lohmann and I had shown was oxidizable to [O2]+ by PtF6," Bartlett says.

The critical experiment suggested itself easily. Bartlett decided to mix PtF6 with xenon and observe what happened. "It had taken a few weeks to order in some xenon," he says, "and because I had no experienced coworkers, I was obliged to prepare all apparatus and PtF6 by myself." Because of his teaching schedule, Bartlett wasn't ready to carry out the experiment until Friday, March 23.

"It took all morning to make my PtF6 and all afternoon to assemble the remainder of the apparatus, test it for leaks, and thoroughly dry it by flaming out the glass and quartz under vacuum," he says. Finally, at about 6:45 PM he transferred his small sample of PtF6 to a sensitive quartz sickle gauge and measured its pressure. He then added xenon into the gauge to roughly the same pressure. "When I broke the seal between the red PtF6 and the colorless xenon, it was about 7 PM," he recalls. "The two gases reacted instantly to precipitate a deep-yellow solid. The measurements indicated that the yellow solid had a composition XePtF6.

"Naturally, I thought that I should share this remarkable result with someone else. There was no one in the building! It appeared that everyone had left for dinner." It took Bartlett two more hours to hydrolyze the sublimed solid to show that it contained xenon, a finding confirmed by his colleague David Frost.

"When I got home, it was about 9:30 PM," Bartlett remembers. "My wife had been anxiously wondering where I was, and dinner was ruined. She is not a chemist, so it took a little while to persuade her that I had an excellent excuse!"

Bartlett is concerned that research in the field may be slowing down because few students are being trained in high-risk research involving elemental fluorine. "Most of the research is being led by chemists in their sixties or older, with less than a handful of younger investigators worldwide leading research groups."

He remains enamored of his field of research, which, he says, "demands not only great care and high experimental skill, but also a spirit of adventure."

Chemical & Engineering News
ISSN 0009-2347
Copyright © 2010 American Chemical Society