Dan LI
,
Yousong GU
,
Zuoren NIE
,
Bo WANG
,
Hui YAN
材料科学技术（英文）
Pseudo-potential and plane wave basis-set under the framework of density functional theory have been employed to study the electronic and magnetic properties of Fe16N2, and to have an insight look on the subject of giant magnetic moments reported in Fe16N2. After geometrical optimization, band structures and densities of states have been evaluated together with the atom resolved band populations and magnetic moments. In this paper, we report a theoretical effort to look into the various aspects of the magnetic properties of Fe16N2, including volume effect and distortion effect.
关键词:
Ab initio calculations
,
磁学性能
,
Fe16N2系统
Zhufeng HOU
,
Aiyu LI
,
Zizhong ZHU
,
Meichun HUANG
材料科学技术（英文）
The electronic structures of CuS2, CuSe2 and CuTe2 with pyrite structures, within the framework the density-functional theory have been investigated. The calculated results explained the recent experimental results which show that there is no clear indication of strong electron correlations in the electronic properties of Cu pyrites, due to the dominant chalcogen p character rather than d characteristic of Cu at the Fermi level.
关键词:
Ab initio calculations
,
null
,
null
Zhufeng HOU
,
Aiyu LI
,
Zizhong ZHU
,
Meichun HUANG
,
Yong YANG
材料科学技术（英文）
SnSb has attracted a great attention in recent investigations as an anode material for Li ion batteries. The formation energies and electronic properties of the Li intercalations in SnSb have been calculated within the framework of local density functional theory and the first-principles pseudopotential technique. The changes of volumes, band structures, charge density analysis and the electronic density of states for the Li intercalations are presented. The results show that the average Li intercalation formation energy per Li atom is around 2.7 eV.
关键词:
SnSb
,
null
,
null
,
null
Dong CHEN
,
Jingdong CHEN
,
Yinglu ZHAO
,
Benhai YU
,
Chunlei WANG
,
Deheng SHI
金属学报(英文版)
doi:10.1016/S1006-7191(08)60082-4
The equilibrium lattice parameter, relative volume V/V0, elastic constants Cij, and bulk modulus of titanium nitride are successfully obtained using the ab~initio plane-wave pseudopotential (PW-PP) method within the framework of density functional theory. The quasi-harmonic Debye model, using a set of total energy vs molar volume obtained with the PW-PP method, is applied to the study of the elastic properties and vibrational effects. We analyze the relationship between the bulk modulus and temperature up to 2000 K and obtain the relationship between bulk modulus B and pressure at different temperatures. It is found that the bulk modulus B increases monotonously with increasing pressure and decreases with increasing temperature. Moreover, the Debye temperature is determined from the non-equilibrium Gibbs functions.
关键词:
Elastic constants
,
null
,
null
,
null
张敏平
,
王广涛
低温物理学报
利用基于密度泛涵的平面波赝势方法,研究了Cs2AgF4中Jahn-Teller（JT）畸变导致的轨道有序,以及铁磁态存在的机制.通过比较各种磁性态的总能和原胞实空间的电荷分布,我们发现：因为在a-b平面内Ag-F键长存在长短不同的交替变换,所以Ag的4d电子会交替占据dz2-x2和dz2-y2轨道.这种相互正交的轨道有序态使体系稳定到铁磁态.同时还发现当增大Jahn-Teller畸变大于0.03时会使层内反铁磁成为基态,这提示人们可以通过增大压力或掺杂等方法提高Jahn-Teller畸变,从而实现层内反铁磁的Cs2AgF4,而这种层内反铁磁态有可能出现超导.
关键词:
第一原理计算
,
磁性
,
超导
