First principles investigation on the ultra‐incompressible and hard TaN
First principles investigation on the ultra‐incompressible and hard TaN
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DOI：
10.1002/jcc.21234
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发表时间：
2009-11
影响因子：
3
通讯作者：
E. Zhao;B. Hong;J. Meng;Zhijian Wu
中科院分区：
文献类型：
--
作者：
E. Zhao;B. Hong;J. Meng;Zhijian Wu
利用密度泛函理论（DFT）研究了TaN的结构、电子和力学性质。考虑了八种结构，即，六方WC、TaN、NiAs、纤锌矿和CoSn结构、立方NaCl、Zn-Cu和CsCl结构。结果表明，在所考虑的结构中，TaN型结构中的TaN在环境条件下最稳定。在5 GPa以上，WC型结构的TaN在能量上成为最稳定的相。它们在机械性能和机械性能方面也是稳定的。在所考虑的结构中，WC型TaN具有最大的剪切模量243 GPa和大的体积模量337 GPa。体积可压缩性略大于金刚石，但在0至100 GPa的压力下小于c-BN。沿c轴的压缩性沿着小于金刚石和c-BN两者的线性压缩性。估计硬度为34 GPa。因此，WC型结构中的TaN是超不可压缩和坚硬的潜在候选者。TaN在WC型结构中的独特机械性能使其适用于极端条件下的应用。© 2009 Wiley Periodicals，Inc.《计算化学杂志》，2009年
The structural, electronic, and mechanical properties of TaN were investigated by use of the density functional theory (DFT). Eight structures were considered, i.e., hexagonal WC, TaN, NiAs, wurtzite, and CoSn structures, cubic NaCl, zinc‐blende and CsCl structures. The results indicate that TaN in TaN‐type structure is the most stable at ambient conditions among the considered structures. Above 5 GPa, TaN in WC‐type structure becomes energetically the most stable phase. They are also stable both thermodynamically and mechanically. TaN in WC‐type has the largest shear modulus 243 GPa and large bulk modulus 337 GPa among the considered structures. The volume compressibility is slightly larger than diamond, but smaller than c‐BN at pressures from 0 to 100 GPa. The compressibility along the c axis is smaller than the linear compressibility of both diamond and c‐BN. The estimated hardness is 34 GPa. Thus, TaN in WC‐type structure is a potential candidate to be ultra‐incompressible and hard. The unique mechanical properties of TaN in WC‐type structure would make it suitable for applications under extreme conditions. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009