B1结构MoN和WN晶体的总能及体弹性模量的计算

本文利用局域密度泛函理论和LMTO ASA方法计算了BI结构的MoN和WN的总能-体积曲线,得到体弹性模量,以及MoN和WN的平衡格常数A_0分别为0.418nm和0.419nm,与实验值符合.并用LMTO-ASA力定理计算了电子波压力,由此讨论了晶体的化学键性质.在总能及电子压力计算中,都采用了与原子球同比例的Muffin tin球面上有效势相等的原则来选定不同原子球半径比,均得到较好的结果.

Calculation of Total Energy and Bulk Modulo for Bl-MoN and Bl-WN Crystals

The total energy curves of Bl-WN and Bl-MoN crystals as a function of relative volume have been calculated by the LMTO-ASA method based on local density functional theory, thereby obtaining the equilibrium lattice constant Aa and the bulk moduli B0, A0 are 0,419 nm and 0 418 nm for WN and MoN respectively, in good agreement with the available experimental data. The corresponding B0 are 3 85 Mbar and 3.81 Mbar. The values of B0 indicate that both crystals bear very high hardness In addition, the electronic Pressure for these crystals have been calculated by using the LMTO-ASA force theorem, and the Properties of chemical bond were discussed, The suce-ssful calculations have shown the availability in the choice of atomic sphere radii in compounds from the equity condition for effective Potential on the surfaces of different muffin-tin spheres.