Dynamical Approach to Stability

If the AIMD simulation is performed over a sufficiently long time, it is possible to compute the dynamical structure factor S q, w) for frequencies ranging from l/T,T being the total simulation time, and 1/t, t being the simulation time step, and for q 

The fact that GeTe is getting more stressed-rigid upon doping is not the only parameter that influences the stability of the compound. If we compute the vibrational density of states by performing a Fourier transform of the velocity autocorrelation function computed for the AIMD trajectory, we obtain curves plotted in Fig. 18.16. As already found experimentally [62], amorphous GeTe is at the same time elastically 

Kohara, S. Kimura, K. Kobayashi, M. Ttikata, T. Matsunaga, R. Kojima, 

Lencer, M. Salinga, B. Grabowski, T. Hickel, J. Neugebauer, M. Wuttig, Nat. Mater. 7(12), 

Welnic, S. Botti, L. Reining, M. Wuttig, Phys. Rev. Lett. 98236403 (2007) 

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