Temperature influence on the valence Compton profiles of aluminum and lithium - art. no. 094301

We present temperature-dependent valence Compton profiles of single-crystal line Al and Li measured with 30 keV incident energy and 173 degrees scatter ing angle with momentum space resolution of 0.1 a.u. The valence profiles f or both samples measured at low temperature are above the high-temperature ones at momentum p(z)approximate top(r), the Fermi momentum, and below at p (z)=0 a.u., which corresponds to a narrowing of the valence Compton profile s with increasing temperature. This fundamental temperature dependence can be attributed to the variation of the lattice constant and thus the variati on of the Fermi momentum with temperature when the experimental results are compared with jellium calculations of the valence Compton profiles utilizi ng a correlation corrected occupation number density. In addition the Li ex periment shows a significant temperature dependence even fur p(z)>p(F), whi ch is assigned to the diminished contribution of higher momentum components to the valence Compton profile with increasing temperature. The Li results are in good agreement with calculations using an empirical temperature-dep endent local pseudopotential.