Positron annihilation studies in binary solid solutions of metal betadiketonates, using lifetime and doppler broadening spectroscopies.

Abstract

Positron annihilation lifetime (LS) and Doppler broadening annihilation kadiation lineshape (DBARL) spectroscopies measurements were performed in several binary solid solutions of the general formula M(l-x,Gfx,L,3 where M = Al(II1) , Ga(II1) , or In(II1) , as matrix; G = Cr (111) , Mn (111) , Fe (111) , co (111) , Ru (111) , Rh(III), and Ir(III), as guest molecules, L = acetylacetone (acac) or dipivaloylmethane (dpm), and X = guest molecule mole fraction. The studied systems can be classified in two groups: the first one presenting only inhibition of positronium formation and the second one presenting inhibition and quenching effects. The inhibition and quenching constants were determined.