Structure and energetics of clean and hydrogenated Ni surfaces and symmetrical tilt grain boundaries using the embedded-atom method
Structure and energetics of clean and hydrogenated Ni surfaces and symmetrical tilt grain boundaries using the embedded-atom method
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使用嵌入原子方法研究清洁氢化镍表面和对称倾斜晶界的结构和能量学
DOI：
10.1103/physrevb.68.245402
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发表时间：
2003
影响因子：
3.7
通讯作者：
H. Kaburaki
中科院分区：
文献类型：
--
作者：
M. Shiga;M. Yamaguchi;H. Kaburaki
多层弛豫，表面/界面能，和氢结合的网站和能量进行了系统的研究，使用嵌入原子的方法，为一系列的清洁和氢化Ni表面和对称倾斜Ni晶界。氢结合能在2.7-2.9 eV的范围内的表面网站，而2.1-2.6 eV的晶界网站，都大于在fcc晶体内部网站，2.1 eV。这些数据是一致的，从从头计算的结论，晶间脆化是由氢偏析在镍晶界。结果发现，多层弛豫的Ni在捕获氢在晶界处起着关键作用。
Multilayer relaxations, surface/interface energies, and hydrogen binding sites and energies were systematically studied using the embedded-atom method, for a series of the clean and hydrogenated Ni surfaces and symmetrical tilt Ni grain boundaries. The hydrogen binding energies were in the range of 2.7-2.9 eV at the surface sites while 2.1-2.6 eV at the grain-boundary sites, both being larger than at the fcc crystal interior site, 2.1 eV. These data are consistent with the conclusions from ab initio calculations that intergranular embrittlement is seen by hydrogen segregation at the Ni grain boundaries. It was found that multilayer relaxation of Ni plays a key role in trapping hydrogen at the grain boundaries.