Prediction of ordering in binary transition-metal alloys
Prediction of ordering in binary transition-metal alloys
复制标题
二元过渡金属合金的有序预测
DOI：
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发表时间：
1987
期刊：
影响因子：
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通讯作者：
D. Fontaine
中科院分区：
文献类型：
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作者：
M. Sluiter;P. Turchi;D. Fontaine
提出了一个能成功预测二元过渡金属合金有序度的简单模型。假定有序和无序态的电子态密度(DOS)均为矩形，且DOS的前四阶矩在有序时保持不变。然后，可以独立于晶格的性质来计算有序能Delta U。由Delta U的符号和大小给出的有序趋势被绘制在作为浓度和d波段填充的函数的有序图中。计算得到的有序图与用更精细的相干势计算得到的结果符合得很好。在过渡金属合金中实验观察到的绝大多数有序结构都落在这些图中预测的有序区内。
A simple model is presented which can successfully predict ordering in binary transition-metal alloys. Rectangular electronic densities of states (DOS) for both ordered and disordered states are assumed, along with the invariance of the first four moments of the DOS upon ordering. The ordering energy Delta U can then be calculated independently of the nature of the crystal lattice. The ordering tendency given by the sign and magnitude of Delta U, is plotted in ordering maps as a function of concentration and d-band filling. Computed ordering maps are found to be in excellent agreement with those obtained by much more elaborate coherent potential calculations. The overwhelming majority of the ordered structures observed experimentally in transition-metal alloys fall within the predicted ordering regions in these maps.