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1.
本文推导了3d4/3d6离子在D4h对称下5D、3L(L=P,D,F,G,H)和1L(L=S,D,F,G,H)态的哈密顿矩阵元,其中包括晶场、自旋-轨道、自旋-自旋相互作用及Trees’修正.基于这个矩阵,利用完全对角化方法,研究了K2FeF4中Fe2+离子的EPR零场分裂参量D,a,F,所得结果与实验符合很好.将本文结某与以前研究比较证明晶体中Fe2+的低自旋态(3L和1L)对零场分裂的贡献是重要的,尤其对四阶零场分裂参量a和F.进一步研究是必要的。  相似文献   

2.
基于离子簇模型,应用斜方畸变八面体中3d1电子的EPR参量微扰公式,研究了MO2(M=Ti,Ce,Sn)晶体(金红石型)中替位V4 的EPR参量,发现由于V4 取代晶体中阳离子而引起的姜泰勒(Jahn-Teller)效应,将导致杂质离子局部结构形成微小压缩八面体.进一步考虑了配体轨道及旋轨耦合作用和杂质离子周围的畸变对自旋哈密顿参量的贡献,结果与实验符合的更好.  相似文献   

3.
Fe(SPh)4-2是一种局域近三角对称的八面体,Fe2 为中心离子.利用不可约张量理论,建立了3d4/3d6离子三角对称(C3*v)的完全能量矩阵.利用EPR理论获得零场分裂的理论公式,通过对角化完全能量矩阵的方法,计算了基态能级分裂与零场分裂参量(D,F-α),理论结果与实验一致.同时,该物质的光谱结构存在Jahn-Teller效应.  相似文献   

4.
电子顺磁共振谱(electron paramagnetic resonance,EPR)参量对杂质离子局域结构极为敏感,对EPR参量的理论研究可以用来确定材料的离子占位和缺陷结构等.从晶体场理论出发,用高阶微扰公式和晶体结构数据和重叠模型获得晶场参量,计算出Cr3+离子在八面体晶体SrLaAIO4中的的自旋哈密顿参量g因子和零场分裂参量D,计算中所用到的参量由该晶体的光谱和结构数据获得,计算结果和实验数据较为符合,并对计算结果进行了分析.  相似文献   

5.
针对曾谨言等[1]由二体算符ó1αó2β构成自旋力学量完全集的3种基本形式,文章由局域酉变换不变量出发,给出自旋1/2的二粒子体系纯态纠缠态的分类,结果表明有四种基本形式,进一步发现由同一纠缠形式叠加态的纠缠度不变.  相似文献   

6.
以团簇Ni4P作为二元体系Ni-P非晶态合金的局域结构,采用密度泛函理论,在B3LYP/Lanl2dz水平下分别对不同重态下的构型进行优化计算,从HOMO、LUMO轨道贡献、各轨道未成对电子数、磁矩和自旋态密度角度分析发现:Ni、P原子对轨道贡献率受空间结构的影响,但受自旋多重度的影响极小;Ni原子是前线轨道的主要贡献者,P原子对其贡献亦不可忽略,说明催化活性是以Ni原子为主,P原子为辅所提供,且Ni原子最可能为团簇Ni4P的催化活性位点;构型1(4)~2(2)的磁性由d轨道上的自旋向上的α电子贡献,且四重态贡献较二重态更为显著,构型3(4)~3(2)的磁性主要由p轨道贡献;构型1(4)的磁矩分布范围最大,构型2(4)的磁矩分布次之;电子自旋具有不确定性,导致其α、β电子发生部分偏转.  相似文献   

7.
对1550℃下锻烧、空气中淬冷的不同α—~(57)Fe_2O_3含量的3CaO、SiO_2(以下简称C_3S)系列样品进行穆斯堡尔谱研究,确定它的铁离子价态、自旋态、占位情况及其与α—~(57)Fe_2O_3含量的关系,析出相和铁含量的关系。研究结果表明:在氧化气氛中进入C_3S中的铁离子约5%以高自旋Fe~(2+)形态出现,在低铁含量的样品中,尚有8%可能是低自旋二价铁Fe~(II)。这一结果与前人的研究有所不同。此外对铁的占位情况与固溶度的关系、Fe~(2+)的出现提出一些看法。  相似文献   

8.
采用低自旋态(2T2)d5离子在三角对称中的公式, 计算了KNbO3:Ir4+ 晶体的自旋哈密顿参量g因子g//,g⊥和超精细结构常数A//,A⊥. 计算结果与实验值符合较好. 同时, 计算还获得了Ir4+离子在KNbO3晶体中的缺陷结构信息,对上述结果进行了讨论.  相似文献   

9.
本文给出两个电子的自旋态和各种自旋算符在无耦合表象和耦合表象中的矩阵表示式,也给出在两电子自旋相互作用可以忽略的条件下的另一种数学表示方式,即把两个电子的自旋态表示为两个二行一列矩阵(一个电子的自旋态矢量)并列的写在了一起.  相似文献   

10.
用双自旋 轨道耦合参数模型研究了四面体四角晶位中络离子CoX2 -4 (X =Cl,Br)的零场分裂D .研究表明 ,配体Br对Co2 离子零场分裂D的影响较大 .  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

15.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

16.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

17.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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