Abstract
We show that the high-temperature Ni(001) surface undergoes a large vertical expansion. Low-energy electron diffraction experiments indicate that the surface thermal-expansion coefficient increases rapidly between 900 and 1300 K, reaching a value nearly 20 times larger than in the bulk. These results directly confirm that a large anharmonicity in the interatomic potential develops on metal surfaces and that it may be a precursor to various surface disordering transitions.
- Received 24 May 1990
DOI:https://doi.org/10.1103/PhysRevLett.65.2808
©1990 American Physical Society