HYDROGEN-RELATED MOLECULAR-STRUCTURES OBSERVED IN F-19-TDPAD STUDIES IN DIAMOND

TDPAD studies of F-19 recoil-implanted into (natural) diamond, show no t less than three characteristic sites populated by F-19 in the diamon d lattice; Two are distinctive lattice locations, but the third is ide ntified as having a broadly distributed and randomly oriented electric field gradient, with a quadrupole coupling constant consistent with t hat of a H-F bond. The fraction of F-19 ions in this third configurati on shows a systematic dependence on the dose of protons used in the re coil implantation process. The interpretation of this phenomenon is as sisted by comparison of data for bulk solid diamond (natural and synth etic), with thin (20 mu m thick) diamond, and also concurrent nuclear reaction analysis determination of the bulk hydrogen concentration in the sample. In-beam TDPAD is shown as able to give a dynamic insight i nto beam induced molecular re-arrangements in the TDPAD time window im mediately following recoil implantation.