School of Chemistry, The University of Sydney, NSW 2006, Australia.
J Phys Condens Matter. 2012 Jun 20;24(24):245102. doi: 10.1088/0953-8984/24/24/245102. Epub 2012 May 15.
The free energies of six crystal structures associated with Cu-Zr alloys-Cu (face centred cubic), Cu(2)Zr, Cu(10)Zr(7), CuZr, CuZr(2) and Zr (hexagonal close packed)-are calculated using the embedded atom potential of Mendelev et al (2009 Phil. Mag. 89 967). We find that the observed low temperature stability of the Cu(10)Zr(7) and CuZr(2) phases is not reproduced. Instead, the model predicts that the CuZr phase remains stable down to T = 0 K. This discrepancy is largely removed when the interaction potentials are cut off at a short distance, such as that used by Duan et al (2005 Phys. Rev. B 71 224208). We present evidence, however, that the cut-off distance necessary to achieve the change in phase stability results in pathological artefacts in the energetics of some crystal phases.
使用 Mendelev 等人（2009 年《Phil. Mag.》89 967）提出的嵌入原子势，计算了与 Cu-Zr 合金相关的 6 种晶体结构（面心立方 Cu、Cu2Zr、Cu10Zr7、CuZr、CuZr2 和六方密排 Zr）的自由能。我们发现，观察到的 Cu10Zr7 和 CuZr2 相在低温下的稳定性无法重现。相反，该模型预测 CuZr 相在 T=0 K 时仍然稳定。当相互作用势在短距离处截断时，例如 Duan 等人（2005 年《Phys. Rev. B》71 224208）所使用的那样，这种差异在很大程度上消除了。然而，我们提出的证据表明，为了实现相稳定性的变化而需要的截断距离会导致某些晶体相的能量学中出现病态的人为产物。
