A PAC experiment was performed on a
181Hf
Ta sample which contained
0. 1 at.
oxygen and
1 at.
hydrogen. At low temperature a new quadrupole interaction with
Q=470 MHz,
=0.95 was found. This interaction is attributed to an O-H complex. At 55 K this interaction disappears and the well known oxygen frequency shows up, indicating a breakup of the O-H pair at 55 K. With deuterium instead of hydrogen the same frequency but a different (105 K) breakup temperature was found.
The financial support of the Bundesminster für Forschung und Technologie is gratefully acknowledge.