Interaction of carbon, nitrogen and oxygen with vacancies and solutes in tungsten
Interaction of carbon, nitrogen and oxygen with vacancies and solutes in tungsten
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碳、氮和氧与钨中的空位和溶质的相互作用
DOI：
10.1039/c4ra13854f
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发表时间：
2015-03
期刊：
影响因子：
3.9
通讯作者：
G.-N. Luo
中科院分区：
文献类型：
--
作者：
C. S. Liu;Q. F. Fang;J. L. Chen;G.-N. Luo
研究钨中的碳、氮和氧等杂质的行为对于了解化合物的形成至关重要，这些化合物可以显著影响钨的物理和化学性质。用密度泛函理论方法研究了小团簇VacXn、SolXn和SolVacXn（Vac =空位，Sol =溶质，X = C，N或O）的几何和能量，探讨了X在钨中的聚集.我们发现空位和溶质空位对X原子有很大的吸引力，多个X原子可以嵌入缺陷中。空位中有4个C原子偏聚形成正方形，形成C-C键，键长为1.58 A，但空位中很难形成N-N（或O-O）键，最多可捕获6个N（或O）原子。钛、钽、铌和锇等溶质对X原子的吸引力较弱，溶质与X原子的结合能依赖于Sol-X的键长。此外，利用质量作用定律确定了VacCn（SolCn）的浓度演化规律，结果表明VacCn（SolCn）的浓度强烈依赖于温度、空位（Sol）和C的初始浓度. SolVacXn的结合能与含有SolVacXn的体系和不含缺陷的体系的体积差线性相关。钨的微观结构中X原子的聚集，形成高X浓度区，可能有助于化合物的形成。
Investigating the behaviors of impurities such as carbon, nitrogen and oxygen within tungsten is crucial to understanding the formation of compounds which can substantially influence the physical and chemical properties of tungsten. Using density functional theory method, we have investigated the geometry and energetics of small VacXn, SolXn and SolVacXn (Vac = vacancy, Sol = solute, and X = C, N or O) clusters to probe the aggregation of X in tungsten. We find that vacancy and solute–vacancies show great attraction to X atoms and multiple X atoms can be embedded in the defects. Four C atoms segregate in a vacancy forming a square where the C–C bond forms with the bond length of 1.58 A, however, it is hard to form N–N (or O–O) bonds in a vacancy although up to six N (or O) atoms can be trapped in a vacancy. The solutes titanium, tantalum, rhenium and osmium present relatively weak attraction to X atoms, and the binding energies of the solute with X rely on the bond length of Sol-X. Moreover, the concentration evolution of VacCn (SolCn) is determined through the law of mass action, and the results show that the concentrations of VacCn (SolCn) depend strongly on temperature, and the initial concentrations of vacancy (Sol) and C. The binding energy of SolVacXn correlates linearly with the volume difference of the system containing a SolVacXn and that with no defects. The aggregation of X atoms in the microstructure of tungsten, forming high X concentration zones, may facilitate the formation of compounds.
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影响因子：
9.4
作者：
Counts, W. A.;Wolverton, C.;Gibala, R.
通讯作者：
Gibala, R.
影响因子：
1.5
作者：
Retsuo Kawakami;T. Shimada;Y. Ueda;M. Nishikawa
通讯作者：
Retsuo Kawakami;T. Shimada;Y. Ueda;M. Nishikawa
影响因子：
3.7
作者：
Kresse, G;Furthmuller, J
通讯作者：
Furthmuller, J
影响因子：
3.7
作者：
N. K. Arkhipova;S. M. Klotsman;I. P. Polikarpova;G. N. Tatarinova;A. Timofeev;L. M. Veretennikov
通讯作者：
N. K. Arkhipova;S. M. Klotsman;I. P. Polikarpova;G. N. Tatarinova;A. Timofeev;L. M. Veretennikov
影响因子：
3.3
作者：
Y. Ueda;T. Shimada;M. Nishikawa
通讯作者：
Y. Ueda;T. Shimada;M. Nishikawa