Influence of the exchange and correlation functional on the structure of amorphous Ge2Sb2Te5

Models of the amorphous phase of Ge2Sb2Te5 have been generated by density functional molecular dynamics simulations with the Becke-Lee-Yang-Parr (BLYP) exchange-correlation functional. Four independent 459-atom models have been used to improve the statistical analysis of the structural properties with respect to previous work by Kim et al. [J. Appl. Phys. 113, 134302 (2013)]. Structural, electronic, and vibrational properties of the BLYP models turn out to be very similar to those generated previously with the Perdew-Burke-Ernzerhof (PBE) functional mostly used in the simulations of phase change compounds. Only a very marginal increase in the fraction of tetrahedra is observed in the BLYP models.