"I should like to do some work (with Professor Yost) in an attempt to prepare certain compounds of xenon suggested by theoretical
arguments. No doubt your xenon is precious; if, however, you could lend us 10 cc or so (of not necessarily pure stuff), we
would try to return it to you either as such or in some compound (I hope), and we would be properly grateful."
Linus Pauling. Letter to Fred Allen. September 13, 1932.