@article{31829, author = {Kristin Einarsdotter and Babak Sadigh and Goran Grimvall and Vidvuds Ozolin{\v s} and Kristin A Persson}, title = {Phonon Instabilities in fcc and bcc Tungsten}, abstract = {

The lattice dynamics of bcc and fcc W is studied as a function of pressure using the density-functional linear-response theory. At high pressures and\ $T = 0$ \ K, bcc W has a higher enthalpy than the fcc and hcp phases and it develops phonon softening anomalies related to this thermodynamic instability; however, it remains dynamically stable. In contrast, the widely unstable shear modes of fcc W at zero pressure (when\ $HfccW\>HbccW$ ) stabilize with increasing pressure before\ $HfccW\<HbccW$ . Hence the thermodynamic and dynamic instabilities are uncorrelated.

}, year = {1997}, booktitle = {Physical Review Letters}, journal = {Physical Review Letters}, series = {Physical Review Letters}, volume = {79}, pages = {2073 - 2076}, month = {09/1007}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.79.2073}, language = {eng}, }