POSITRON-ANNIHILATION IN CU AND DILUTE CUSB AND CUIN ALLOYS

The vacancy formation enthalpy in copper, CuSb (0. 1 at. % and 0. 5 at. %) and CuIn (0. 5 at. %) has been studied by measurements of the temperature dependence of the Doppler broadening of the positron annihilation photon line. Not only monovacancy formation enthalpies E**f//v have been deduced from the data but also the vacancy-solute-atom binding energy E**f//v. The extracted vacancy formation enthalpy for copper is E**f//v equals 1. 29 plus or minus 0. 03 ev. The value for the vacancy-indium binding energy is E**b//v//I//n equals 0. 29 plus or minus 0. 06 ev. For a vacancy-antimony pair one finds E**b//v//S//b equals 0. 32 plus or minus 0. 06 ev.