Abstract
Using a first-principles method, I have studied the static and vibrational properties of the lonsdaleite-silicon. The frequencies of the Raman active modes of the lonsdaleite-Si at ambient pressure agree very well with the experimental results. Among these Raman active modes, the (Formula presented) mode can be an indication mode of the lonsdaleite-Si. The high-pressure behavior of the zone-center modes of the lonsdaleite-Si is first studied and a pressure-induced mode softening is found. The (Formula presented) mode of the lonsdaleite-Si exhibits red shift under compression and its frequency decreases to zero as the applied pressure increases to around 14 GPa. The pressure-induced mode softening of the (Formula presented) mode indicates that the lonsdaleite-Si has a phase transition before the applied pressure reaches 14 GPa.
| Original language | English |
|---|---|
| Pages (from-to) | 5-8 |
| Number of pages | 4 |
| Journal | Physical Review B - Condensed Matter and Materials Physics |
| Volume | 61 |
| Issue number | 1 |
| DOIs | |
| State | Published - 2000 |
| Externally published | Yes |