@article{31829, author = {Kristin Einarsdotter and Babak Sadigh and Goran Grimvall and Vidvuds Ozoliņš 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 $H_{W}^{fcc} > H_{W}^{bcc}$ ) stabilize with increasing pressure before $H_{W}^{fcc} < H_{W}^{bcc}$ . Hence the thermodynamic and dynamic instabilities are uncorrelated.

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