Abstract
The phonon dispersion of chromium has been investigated over a large temperature range. Besides an overall decrease in the phonon frequencies the L2/3(111) mode and the T1[ξξ0] branch exhibit a remarkable softening with increasing temperature. The analysis in terms of a Born-von Kármán force-constant model assuming axial symmetry yields dominating second-nearest-neighbor force constants. Their variation with temperature causes the observed phonon softening. A comparison with other transition metals shows a systematic softening of the shear motion of [111] rows against each other with decreasing d-electron density.
Original language | English |
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Pages (from-to) | 3132-3137 |
Number of pages | 6 |
Journal | Physical Review B |
Volume | 47 |
Issue number | 6 |
DOIs | |
State | Published - 1993 |
Externally published | Yes |