Publications Details
Radial dependence of silicon KVV and L23VV Auger matrix elements
We present calculations which show the radial dependence of the KVV and L12VV Auger matrix elements of silicon. We find greatly differing dependences, converging within ~ 1 a.u. of the nucleus in the case of the KVV, but not until — 4 a.u. in the case of the L23VV, well beyond the bond midpoint of — 2.2 a.u. We also find quite different dependences for the various elements within a particular CVV transition. Because the local density of states (LDOS) is dependent on the radius of the sphere of integration, our results suggest that different CVV Auger processes on the same atom in fact probe different LDOSs, as do even different contributions within the same transition. (This effect is separate from the well-known matrix element property which weights angular-momentum components differently.) These results call into question both the single-site LDOS approximation when used in the interpretation of low-energy ( < 100 eV) Auger spectra, and the application to high-energy spectra of local densities of states obtained by integration over muffin-tin or Wigner-Seitz spheres which have a large radius compared to the region probed by the Auger process. © 1992, American Vacuum Society. All rights reserved.