By using the Born-von Kfirmfin theory of lattice dynamics and the modified analytic embedded atom method, we reproduce the experimental results of the phonon dispersion in fcc metal Cu at zero pressure along three hig...By using the Born-von Kfirmfin theory of lattice dynamics and the modified analytic embedded atom method, we reproduce the experimental results of the phonon dispersion in fcc metal Cu at zero pressure along three high symmetry directions and four oft-symmetry directions, and then simulate the phonon dispersion curves of Cu at high pressures of 50, 100, and 150 GPa. The results show that the shapes of dispersion curves at high pressures are very similar to that at zero pressure. All the vibration frequencies of Cu in all vibration branches at high pressures are larger than the results at zero pressure, and increase correspondingly as pressure reaches 50, 100, and 150 GPa sequentially. Moreover, on the basis of phonon dispersion, we calculate the values of specific heat of Cu at different pressures. The prediction of thermodynamic quantities lays a significant foundation for guiding and judging experiments of thermodynamic properties of solids under high pressures.展开更多
采用改进型嵌入原子法(modifiedembedded atom method,MEAM),计算了(001)Au/(111)Si、(011)Au/(111)Si、(111)Au/(111)Si、(001)Au/(001)Si、(011)Au/(001)Si、(111)Au/(001)Si六个扭转界面的界面能.结果表明,不论是对于(111)Si还是(001...采用改进型嵌入原子法(modifiedembedded atom method,MEAM),计算了(001)Au/(111)Si、(011)Au/(111)Si、(111)Au/(111)Si、(001)Au/(001)Si、(011)Au/(001)Si、(111)Au/(001)Si六个扭转界面的界面能.结果表明,不论是对于(111)Si还是(001)Si基底,相同基底的界面均按照(111)Au/Si、(001)Au/Si、(011)Au/Si顺序依次增加;从界面能的最小化考虑,Au在(111)Si或(001)Si基底上的外延生长,Au(111)面为择优晶面,择优扭转角分别为θ=2.68°和θ=2.42°.展开更多
为了研究膜-基界面对薄膜中晶粒生长以及性能的影响,采用改进嵌入原子法(Modified Embedded Atom Method,MEAM)计算了(001)Ag/(001)Si、(011)Ag/(001)Si、(111)Ag/(001)Si扭转界面的界面能,结果表明:界面能按照(111)Ag/(001)Si,(001)Ag/...为了研究膜-基界面对薄膜中晶粒生长以及性能的影响,采用改进嵌入原子法(Modified Embedded Atom Method,MEAM)计算了(001)Ag/(001)Si、(011)Ag/(001)Si、(111)Ag/(001)Si扭转界面的界面能,结果表明:界面能按照(111)Ag/(001)Si,(001)Ag/(001)Si,(011)Ag/(001)Si的顺序依次增加;从界面能的最小化考虑,Ag的(111)面为择优晶面,择优扭转角为θ为8.16°.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 61078057 and 11204227)the Scientific Research Program of Education Department of Shaanxi Province, China (Grant No. 12JK0958)
文摘By using the Born-von Kfirmfin theory of lattice dynamics and the modified analytic embedded atom method, we reproduce the experimental results of the phonon dispersion in fcc metal Cu at zero pressure along three high symmetry directions and four oft-symmetry directions, and then simulate the phonon dispersion curves of Cu at high pressures of 50, 100, and 150 GPa. The results show that the shapes of dispersion curves at high pressures are very similar to that at zero pressure. All the vibration frequencies of Cu in all vibration branches at high pressures are larger than the results at zero pressure, and increase correspondingly as pressure reaches 50, 100, and 150 GPa sequentially. Moreover, on the basis of phonon dispersion, we calculate the values of specific heat of Cu at different pressures. The prediction of thermodynamic quantities lays a significant foundation for guiding and judging experiments of thermodynamic properties of solids under high pressures.
文摘采用改进型嵌入原子法(modifiedembedded atom method,MEAM),计算了(001)Au/(111)Si、(011)Au/(111)Si、(111)Au/(111)Si、(001)Au/(001)Si、(011)Au/(001)Si、(111)Au/(001)Si六个扭转界面的界面能.结果表明,不论是对于(111)Si还是(001)Si基底,相同基底的界面均按照(111)Au/Si、(001)Au/Si、(011)Au/Si顺序依次增加;从界面能的最小化考虑,Au在(111)Si或(001)Si基底上的外延生长,Au(111)面为择优晶面,择优扭转角分别为θ=2.68°和θ=2.42°.
文摘为了研究膜-基界面对薄膜中晶粒生长以及性能的影响,采用改进嵌入原子法(Modified Embedded Atom Method,MEAM)计算了(001)Ag/(001)Si、(011)Ag/(001)Si、(111)Ag/(001)Si扭转界面的界面能,结果表明:界面能按照(111)Ag/(001)Si,(001)Ag/(001)Si,(011)Ag/(001)Si的顺序依次增加;从界面能的最小化考虑,Ag的(111)面为择优晶面,择优扭转角为θ为8.16°.
