共查询到18条相似文献,搜索用时 187 毫秒
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基于完全对角化方法(complete diagonalization method, CDM), 研究了6 S(3d5)态离子在三角晶场(包括C3v,D3,D3d点群对称晶场)中零场分裂(zero-field splitting, ZFS)参量D和(a-F)的微观起源.研究中除了考虑研究者通常考虑的SO(spin-orbit)磁相互作用外,同
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6 S(3d5)态离子')" href="#">6 S(3d5)态离子
零场分裂参量
磁相互作用
完全对角化方法 相似文献
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基于完全对角化方法,研究了4B1(3d3)态 离子在四角对称晶场中的磁相互作用,分析了自旋哈密顿参量(b02, g∥, g⊥ , Δg)的微观起源.结果表明 :在被考虑的大部分晶场区域,人们通常考虑的SO(spin-orbit)磁相互作用的贡献最为重要 ;然而,对于零场分裂参量b02而言,来自其他机理(包 括SS(spin-orbit),SOO(sp in-other-orbit),SO-SS-SOO)的贡献在大部分晶场区域超过了20%;在部分晶场区域,其 他机理的贡献甚至超过SO机理的贡献.详细地分析了Macfarlane 零场分裂参量b02 近似三阶微扰理论的收敛性,结果表明:该理论在大部分晶场区域收敛性较差.讨论了3d3 态离子第一激发态2Eg分裂的微观起源.并利用 群论方法解 释了在C4v和C3v对称晶场中2Eg< /sub>态分裂的不同机理.
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4B1(3d3)态离子')" href="#">4B1(3d3)态离子
磁相互作用
自旋哈密 顿参量
完全对角化方法(CDM)
微扰理论方法(PTM) 相似文献
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RbMgF3 :Ni2+ 体系晶格局域结构的EPR理论研究 总被引:7,自引:2,他引:5
在考虑掺杂晶体局域畸变的影响后, 建立了联系RbMgF3: Ni2+体系的局域畸变结构与EPR谱间的关系, 并计算了RbMgF3: Ni2+晶体在C3v和D3d对称下的零场分裂参量和g 因数. EPR谱的理论计算值与实验值符合甚好. 相似文献
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采用了中间场耦合图像,考虑了以前研究中被忽略的SS (spin-spin)磁相互作用以及SOO (spin-other-orbit)磁相互作用,利用完全对角化方法,研究了3d2态离子在三角对称 (C3v, D3, D3d)晶体中自旋哈密顿(SH)参量的微观起源.发现自旋哈密顿参量 (包括零场分裂参量D和g因子g∥,g⊥)来自四种耦合机理:(1)SO (spin-orbit)耦合机理; (2) SS耦合机理;(3)SOO
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自旋哈密顿参量
2态离子')" href="#">3d2态离子
三角对称晶场
SS与SOO作用
SO-SS-SOO联合作用机理 相似文献
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本文用X射线多晶衍射方法和差热分析方法研究了LaNi5-xSix(x≤1.25)的相关系,用排水取气法测量了样品的吸H2性能,LaNi5,的固溶体和新的三元化合物LaNi4Si形成共晶体系,共晶温度1170℃,共晶点x=0.96,在单相区中LaNi5,相点阵常数随Si替代量增加,a减小,c增大,三元化合物LaNi4Si属正交晶系,点阵常数a=8.382?,b=5.210?,c=3.989?。测量密度D0=7.59g/cm3,每单胞含两个化合式单位,可能的空间群为D2h5,C2v2和C2v4,它具有可逆的吸放H2性能,吸H2后形成氢化物LaNi4SiH3.6。La1-ySiyNi,系列样品吸H2量随Si含量增加而很快下降,LaNi5-xSix系列样品吸H2量随Si含量的增加稍略下降,平台压力也下降,LaNi4.8Si0.2的生成自由能为476cal/molH2,固溶体氢化物的稳定性比LaNi1高。
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KCdF3晶体中Cr3+-Li+中心局域结构研究 总被引:2,自引:0,他引:2
利用零场分裂参量与晶体结构之间的定量关系,研究了双掺杂晶体KCdF3:Cr3+,Li+的局域结构。指出,对于KCdF3:Cr3+,Li+晶体,四角晶场的形成包含两个方面:(1)由于电荷补偿而产生的等效电荷形成的四角对称晶场;(2)Cr3+的局域结构发生晶格畸变而产生的四角对称晶场。事实上,当Cr3+和Li+掺入KCdF3晶体时,Cr3+代替了Cd2+离子;由于Cr3+离子与Cd2+离子的半径不同、电荷不同、质量不同,导致Cr3+的局域结构发生晶格畸变,由此而产生四角对称晶场;由于电荷补偿,Li+离子取代了[001]方向与Cr3+离子邻近的Cd2+离子,由此产生的等效电荷而形成的四角晶场。这样,Cr3+的局域结构由Oh对称变为C4v点对称。文中建立了ZFS参量和晶体结构之间的定量关系。在考虑晶格畸变和等效电荷的基础上,研究了KCdF3:Cr3+,Li+晶体的ZFS参量,理论结果和实验符合很好。得到了F-离子向中心离子分别移动为ΔR1=0.00268nm,ΔR2=0.001nm,ΔR3=0.00165nm。 相似文献
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Zi-Yuan Yang 《Journal of luminescence》2007,126(2):753-758
An extended complete diagonalization method/microscopic spin-Hamiltonian (CDM/MSH) program has been developed, which is applicable for d3 ions at sites of tetragonal symmetry type I (C4v, D2d, D4, D4h) and trigonal symmetry type I (C3v, D3, D3d). The Hamiltonian includes the spin-spin (SS) and spin-other-orbit (SOO) magnetic interactions besides the spin-orbit (SO) magnetic interaction usually taken into account. Utilizing the extended CDM/MSH program, the optical spectra, the spin-Hamiltonian (SH) parameters of the ground state 4B1, and the splitting δ(2E) of the first excited 2E state for Cr3+ (3d3) ions at C4v symmetry sites in MgO crystals have been successfully investigated. It is found that although the SO magnetic interaction is the most important one, the contributions to the SH parameters and the optical spectra from the SS and SOO magnetic interactions for Cr3+:MgO crystals are appreciable and should not be omitted, especially reaching 27.8% for the zero field splitting parameter D. 相似文献
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We present tables of the characters of the irreducible nonequivalent loaded corepresentations of the point groups C0, C2, S2, Ch, C3, C4, S4, C2v, C2h, D2 C6, S6, C3h, C3v, D3, C4h, C4v, D4, D2d, C6h C6v, D3d. D6, D3h, T, Th, Td O and Oh.Translated from Izvestiya VUZ. Fizika, Vol. 11, No. 11, pp. 23–34, November, 1968. 相似文献
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THEORETICAL RESEARCH ON OPTICAL,THERMAL AND MAGNETIC PROPERTIES OF DICHLOROTETRAPY-RAZOLENICKEL(TYPE II)COMPLEX 下载免费PDF全文
In this paper, we have calculated and analyzed theoretically and consistently the absorption spectra, the ZFS and EPR parameters of the ground state, the Schottky low-temperature heat capacity, and the paramagnetic susceptibility of Ni(pz)4Cl2 (Dichlorotetrapyrazolenickel) complex by using d8[(1-C2)D*4h+C2D*2h] complete configuration mixing unified crystal field theory. The theoretical results agree with the experimental observation very well. We can give a complete and reasonable theoretical interpretation of the optical, thermal and magnetic properties of Ni(pz)4Cl2. 相似文献
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K.S. Aleksandrov L.S. Emelyanova S.V. Misjul I.T. Kokov 《Solid State Communications》1985,53(10):835-839
Structural phase transition in Rb2CdCl4: Mn2+ single crystal has been found near 133 K by EPR, X-ray and optical methods. Octahedral tilt system in the low temperature phase corresponds to the symmetry change D174h → D182h or D174h → C62h. 相似文献
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EPR study of Cr3+-doped tetramethyl cadmium chloride (TMCC) single crystals is carried out at room temperature. The crystal field and spin-Hamiltonian parameters are evaluated from the resonance line positions of different lines observed in the EPR spectra. The g and D parameter values are found to be g=1.9741±0.0002 and D=553±2×10−4 cm−1, respectively. EPR data indicate that the site symmetry of Cr3+ ion in the crystal is distorted octahedron. Cr3+ ions enter the lattice substitutionally replacing Cd2+ sites and bind to the neighboring extra Cd vacancies necessary for charge compensation. The optical absorption spectra are measured in 195–925 nm wavelength range at room temperature. From optical study the energy values of different orbital levels are estimated. Further, the bonding parameters are obtained by correlating optical and EPR data and the nature of bonding in the crystal is discussed. The values of Racah parameters (B and C), crystal field parameter (Dq) and nephelauxetic parameters (h and k) are obtained to be B=722, C=2845, Dq=2043 cm−1, h=1.015 and k=0.21. 相似文献
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测量和分析了不同温度下Eu3+:ThO2的激发光谱、发射光谱和荧光 衰减曲线.Eu3+:ThO2晶体是用熔融法生长的.通过12K下格位选择激 发下的发射光谱测量,利用晶场理论,确定了Eu3+在ThO2占据Oh和C3v两种格位.列表给出了两种格位Eu3+离子的晶场能 级和室温及12K下的荧光寿命.讨论了温度对能 相似文献