THAT stand-offish element argon has been persuaded to consort with other
atoms for the first time. Marku Räsänen and his colleagues at the
University of Helsinki in Finland have created a novel compound called hydrogen
argon fluoride (HArF).
To do it, they had to freeze argon by chilling it to just 10 degrees above
absolute zero, add hydrogen fluoride—an acid capable of eating through
glass—and fire lasers at the mixture while warming it slightly
(Nature, vol 406, p 874). “We’re now down to just two noble gases in the
periodic table—helium and neon—that don’t…
