Temperature displacement of X-ray absorption fine structure in aluminium

Measurements in the low-energy fine-structure region adjoining the K absorption edge of aluminium have revealed a change in energy position of the pronounced 29 eV absorption minimum on lowering the temperature from 293 to 77 K. This displacement was about three times larger than expected from thermal contraction of the lattice. It is inferred from these observations that at low temperatures a decrease may occur in η( k ), the term representing, in the Kozlenkov theory, the effect of the field of the absorbing atom upon the wave of the ejected electron