排序方式: 共有28条查询结果,搜索用时 31 毫秒
1.
2.
利用基于密度泛函理论平面波赝势法的第一性原理计算,研究了过渡金属化合物OsB2和OsO2的金红石相、黄铁矿相与萤石相三种结构在高压下的状态方程和结构特性以及OsO2可能的高压相变.理论计算结果支持OsB2与OsO2的萤石相是潜在超低可压缩性的硬性材料.同时,也分析了它们的电子结构,力求理解大体变模量和高硬度的微观机制.结果表明,可以利用过渡金属高的价电子浓度,掺入硼、氧、碳、氮等轻的元素形成强的方向键,这可能提供了一种合成超硬材料的新途径. 相似文献
3.
4.
5.
凝聚态物理一个重要的研究内容就是,发现新物态,标识新物态,观测、理解并调控它所具有的物理性质以及不同物态之间的相互转变。日常生活中常见的固态、液态和气态就是三种不同的物态。而无处不在的导电金属和不导电的绝缘体又是另外一种物态分类方式。固体能带理论告诉我们,这是通过对固体中电子的排布方式进行分类的。电子在周期性的固体中呈现能带结构,泡利不相容原理使得每个能带只能填充两个自旋反向的电子。再根据能量最低原理,电子按能量高低次序填充能带,如果恰好填满某个能带,与最低未占据能带之间存在有限大小的能量间隙,那就是绝缘体; 如果有能带未填满,部分占据,那就是金属。 相似文献
6.
站立在物理所所史展大厅,凝望着一幅幅珍贵的历史照片和一件件陈旧的仪器实物,我感慨万千。“千磨万击还坚劲,任尔东西南北风。”物理所风雨磨砺、坚韧不拔的历史,镌刻在了90 年前开始的岁月里……漫长的艰难足迹,不仅折射出物理学科在我国生根、发芽、发展、壮大的宏伟篇章,也印证了中国基础科学研究从无到有、由弱渐强的战略征程。 相似文献
7.
8.
STUDIES ON THE NEXT-NEAREST NEIGHBOR HOPPING INTERACTIONS OF π-ELECTRONS IN QUASI-ONE-DIMENSIONAL ORGANIC FERROMAGNETIC MODEL
下载免费PDF全文
![点击此处可从《中国物理》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Based on a theoretical model proposed for quasi-one-dimensional organic polymer fer-romagnets, the next-nearest neighbor hopping interactions of sr-electrons are considered. Allowing for full lattice relaxation, a set of self-consistent equations is established to study the system. The spin-density-wave (SDW) and the possible ferromagnetic ground state of the system are investigated in detail. It is found that the next-nearest neighbor hopping in-teractions will make the SDW stronger and consequently make the ferromagnetic state more stable as compared with the nonmagnetic reference state. 相似文献
9.
We propose an efficient implementation of combining dynamical mean field theory(DMFT) with electronic structural calculation based on the local density approximation(LDA).The pseudo-potential-plane-wave method is used in the LDA part,which enables it to be applied to large systems.The full loop self consistency of the charge density has been reached in our implementation,which allows us to compute the total energy related properties.The procedure of LDA+DMFT is introduced in detail with a complete flow chart.We have also applied our code to study the electronic structure of several typical strong correlated materials,including cerium,americium and NiO.Our results fit quite well with both the experimental data and previous studies. 相似文献
10.