The grain-boundary regions of nanophase Cu were investigated by using X-ray absorption fine-structure techniques. It was noted that typical samples which were made by using standard techniques had to be greatly thinned, if studied in transmission, so as to eliminate experimental artefacts which might appear to lower the apparent coordination number. In order to avoid this problem, the samples were measured by using the total electron yield technique. The results indicated a grain boundary structure which, on average, was similar to that in conventionally prepared polycrystalline Cu. This contradicted previous X-ray absorption fine-structure measurements which had been made under transmission conditions and which had indicated a lower coordination number.

E.A.Stern, R.W.Siegel, M.Newville, P.G.Sanders, D.Haskel: Physical Review Letters, 1995, 75[21], 3874-7