An electron transfer mechanism for ultrasonic attenuation in metals

✍ Scribed by C. Kittel

• Publisher: Elsevier Science
• Year: 1955
• Weight: 379 KB
• Volume: 3
• Category: Article
• ISSN: 0001-6160
• DOI: 10.1016/0001-6160(55)90070-5

✦ Synopsis

This is a striking example of the effect of a Brillouin Zone overlap on the lattice constant of a solution since addition of divalent magnesium to monovalent lithium increases the electron-atom ratio. It may be readily shown4 that the first Brillouin Zone overlap in the BCC structure occurs at e/&%1.5 and it is known that attending the overlap an expansion of the lattice may occur normal to the bounding planes of the first Zone. The bounding planes in the BCC structure are 110 planes and such an expansion would be thus expected to produce general expansion of the lattice. If both the lithium and the magnesium are fully ionized, the electron-atom ratio of 1.5 is reached at 50 atomic per cent magnesium and Fig. 1 shows that it is indeed at this point that the lattice begins to expand, reversing the previous trend. Some of the earlier data are included for comparison.