三种不同表象下多组态含时Hartree Fock理论实现方案

多组态含时Hartree Fock 理论方法作为一种研究强激光场中多电子原子分子体系动力学行为的一种有效手段, 近几年来备受关注. 本文介绍了该方法的发展历史, 重点介绍了本研究组近几年来对该理论方法的发展, 以及多组态含时Hartree Fock理论方法在原子基函数表象、 格点表象、 二次量子化表象不同的实现方案, 并就典型体系做了大量详细的计算. 同时也详细介绍了该方法在实际应用中存在的挑战, 展望了多组态含时Hartree Fock理论方法的发展应用前景. 关键词： 强激光场 多电子动力学 电子相关     

类镍离子（HfXL V —— ReXL VIII）能级和振子强度的理论计算

 利用多组态Hartree–Fock–Relativistic (HFR)理论系统地从头计算了类镍离子（HfXL V-ReXL VIII）的能级、电偶极跃迁波长和振子强度。计算结果与实验符合得较好，为我们的高Z元素激光等离子体光谱实验分析提供了重要依据。     

类镍离子（HfXL V -- ReXL VIII）能级和振子强度的理论计算

利用多组态Hartree–Fock–Relativistic (HFR)理论系统地从头计算了类镍离子（HfXL V-ReXL VIII）的能级、电偶极跃迁波长和振子强度。计算结果与实验符合得较好,为我们的高Z元素激光等离子体光谱实验分析提供了重要依据。     

用Hartree-Fock-Slater-Boltzmann-Saha模型研究等离子体细致组态原子结构及其状态方程

用平均原子自洽势计算等离子体的自由电子背景，通过在Hartree Fock Slater自洽场原子结构中引入背景修正计算离子组态结构，为Boltzmann Saha方程提供能级参数，再通过调节共同的背景电子实现Saha方程与Hartree Fock Slater方程的耦合，自洽求解等离子体细致组态原子结构，提高Saha方程的计算精度.以碳、铝等离子体作为算例，分析了本方法的适用范围. 关键词： 原子结构 Boltzman Saha方程 状态方程     

PTCDA分子基态的飞秒激光控制研究

将优化控制理论和多组态含时Hartree（MCTDH）方法相结合,建立了适合于MCTDH方法的计算具有平面结构的PTCDA分子的多自由度振动量子模型,研究了在PTCDA分子激发后从分子激发态回落至分子基态的动力学过程.在理论上分析了约化目标态产生率与激发脉冲、分子的演变时间及优化场的有效能量之间的关系,对分子在各个振动坐标下波函数的振动分布做了分析与比较.研究发现,增加分子的回落演变时间在提高目标态产生率的同时可以使优化激光控制场的强度降低,这为实验上用低能量激光最大程度地实现目标态提供了有效手段. 关键词： PTCDA 多组态含时Hartree方法 飞秒激光控制     

自旋极化的同位旋非对称核物质性质

利用Skyrme有效相互作用,采用核子–核子相互作用参数SKM*和SⅢ对自旋极化的同位旋非对称核物质的特性和状态方程进行了研究,讨论了非对称核物质的磁化率随密度的变化关系及其同位旋依赖性.结果表明:在Skyrme Hartree Fock框架内,同位旋非对称核物质会发生从非极化态到极化态的相变,而且发生相变的临界密度随同位旋非对称度增大而降低.另外,还与微观BHF(Brueckner Hartree Fock)的理论预言进行了比较和讨论.     

系统-热库模型平衡约化密度矩阵的精确计算:多层多构型含时Hartree方法及其与多电子态路径积分分子动力学方法的比较（英文）

本文针对以系统-热库模型为特征的开放量子系统提出了一种计算平衡约化密度矩阵的有效而准确的方法.该方法采用多层多构型含时Hartree理论进行虚时演化并使用重点采样程序计算量子系综平均.此方法应用于自旋-玻色子模型哈密顿量,获得了与多电子态路径积分分子动力学方法一致的准确结果.     

同位旋非对称核物质性质与扩展的BHF方法(Ⅰ)同位旋相关的扩展的BHF方法

通过引进基态关联和同位旋自由度的区分,推广了Brueckner Hartree Fock理论方法,并应用于同位旋非对称核物质,系统地研究了在整个同位旋自由度范围内核物质的状态方程和单粒子特性及其同位旋效应.还研究了微观三体核力对同位旋非对称核物质性质及其同位旋效应的影响,定量讨论了三体力效应与相对论性平均场理论及Dirac Brueckner方法的联系.主要给出了同位旋相关的Brueckner Hartree Fock方法的基本理论和计算公式.     

自旋极化中子物质的状态方程

在Brueckner–Hartree–Fock理论框架内,研究了自旋极化的中子物质的状态方程及其自旋依赖性,计算了自旋非对称能及相关的物理量如磁化率和朗道参数G₀,并着重讨论了三体核力的影响,结果表明:在整个自旋极化度范围内,中子物质的每核子能量随自旋极化度的变化都满足二次方规律,自旋对称能随密度单调增加,这意味着中子物质中不会发生由自旋非极化态向自旋极化态的自发相变,三体核力的主要效应是使中子物质磁化率随密度减小的速度加快,从而使中子物质的磁化相变更加困难.     

奇A核101Pd和101Ru的负宇称带能谱研究

将具有正宇称的gds组态空间扩大到包含具有负宇称的1h11/2轨道,采用修正的表面δ相互作用(MSDI)对101Pd和101Ru两个奇A核进行了形变HF计算,得到了基态和一些激发态的解.同时,还用近似角动量投影形变Hartree Fock(PDHF)方法对101Pd和101Ru进行了能谱计算,得到其正、负宇称带的解,计算结果与实验谱基本一致. Using modified delta interaction, enlarging the gds configuration space to include the 1h_11/2 orbital with negative parity, the deformed Hartree Fock calculations for both nuclei: 101Pd and 101Ru are performed. Their ground state and some excited configurations are obtained. The approximate angular momentum projected deform Hartree Fock (PDHF) method is also applied to nuclei 101Pd and 101Ru, and both of their positive and negative parity bands are obtained...     

分子和金表面相互作用的DFT和HF研究之比较

从第一性原理出发,分别利用密度泛函理论和哈特利-福克方法优化了4 ,4-二巯基联苯分子的几何结构,计算了电子结构,讨论了分子与金表面的相互作用.结果表明,在描述分子的电子结构以及分子与金表面的相互作用时,密度泛函理论可以给出更好的结果.     

The Primary Investigation of Ξ-N Skyrme Force Parameters

the parameters of Ξ–n skyrme force are firstly determined according to the experimental data.With these parameters,the Ξ–potential depth,the single particle energy and the root mean square radius of Ξ–hyperon(hypernucleus)are calculated in the skyrme–hartree–fock framework.the results agree well with those of other models.     

Coherent control of the spin current through a quantum dot

Within the weak-coupling regime the spin current through a quantum dot system is calculated using a quantum master equation approach which includes a sum over Matsubara terms. To be able to efficiently calculate, also at low temperatures, the time evolution of the reduced density matrix a high-temperature approximation was derived which proves to be rather accurate in comparison to the exact results. In the present model it is assumed that the energy levels of the dot are split by a constant magnetic field. An additional external (laser) field is used to control the currents of the two spin polarizations. This is either done using the phenomenon of coherent destruction of tunneling or optimal control theory. Scenarios are studied in which the spin current is reversed while the charge current is kept constant.     

Ga_(2n)(n=1～4)团簇自旋极化机理的密度泛函理论研究

利用基于密度泛函理论的第一性原理方法,在广义梯度近似(GGA)下对Ga_(2n)(n=1～4)团簇进行了几何结构优化和结合能计算,并对其电子结构及成键特性进行了分析.结果表明,Ga_2,Ga_4团簇的基态都是自旋极化态,Ga_6团簇的能量局域极小的八面体结构也具有自旋极化;这些团簇的最外层分子轨道的空间分布是对称的,最外层分子轨道之间的能量相差很小,最外层分子轨道的近简并引起了自旋极化;对称性较高的团簇容易形成近简并的最外层分子轨道.     

Spin-resolved transport properties of DNA base multi-functional electronic devices

By using density functional theory in combination with non-equilibrium Green's function method, we have investigated the spin-polarized electronic transport properties of four DNA base devices, namely, adenine (A), cytosine (C), guanine (G) and thymine (T). The results show the spin-polarized transport properties can be effectively regulated by adopting different bases, and thymine based device can exhibit high-efficiency spin-filtering, negative differential resistance, spin rectifying behaviors and switching effect by tuning the external magnetic field. We find that the variation in the degree of localization of the frontier molecular orbitals at different biases is responsible for these interesting phenomena. These effects can be explained by the spin-resolved transmission spectrum and the spatial distribution of molecular orbitals around the Fermi level. Our results suggest that thymine base holds great potential application in designing multi-functional spin molecular device.     

Electronic and Magnetic Properties of the p-NPNN

In this paper, we study the electronic band structure and the ferromagnetic properties of the organic radicalp-NPNN by employing density-functional theory with generalized gradient approximation (GGA) and local-spin densityapproximation (LSDA). The density of states, the total energy, and the spin magnetic moment are calculated. Thecalculations reveal that the δ-phase of p-NPNN has a stable ferromagnetic ground state. It is found that an unpairedelectron in this compound is localized in a single occupied molecular orbital (SOMO) constituted primarily of π* (NO)orbitals, and the main contribution of the spin magnetic moment comes from the π* (NO) orbitals. By comparison, wefind that the GGA is more suitable to describe free radical systems than LSDA.     

Ni^2＋：CsMgCl3的光学吸收谱和EPR的研究

应用三角晶场中d^2(d^8)电子组态包括静电相互作用和自旋－轨道耦合作用的强场能量矩阵,采用完全对角化方法,精确地计算了具有D3d对称的Ni^2 :CsMgCl3的光学吸收谱和EPR谱,理论结果与实验值符合得很好。     

Ni2+:RbMgF3的电子顺磁共振谱的研究

含有过渡金属离子的晶体的光学吸收谱、零场分裂D值和g因子与晶体结构有密切关系,应用Ni^2 的参量化d轨道和三角晶场中d^8电子组态的强场能量矩阵,通过建立完全对角化方法,精确地计算了具有C3ν和D3d两种对称的Ni^2 ：RbMgF3的电子顺磁共振谱,分析了Ni^2 ：RbMgF3的零场分裂D值和g因子与晶体结构参量R和θ的依赖关系。理论值与实验值符合得很好。     

MnFe2O4晶体的基态能级和零场分裂参量

由不可约张量理论构成一个3d4/3d6离子三角(C3V)对称的晶体场和自旋-轨道相互作用哈密顿矩阵,由这个晶体场和自旋-轨道相互作用哈密顿矩阵被完全对角化后能够求出MnFe2O4晶体中的Fe2+离子的电子顺磁共振零场分裂参量D和F-a,计算了低自旋态(3L态)对电子顺磁共振零场分裂参量(D,F-a)的贡献.结果显示低自旋3L态对电子顺磁共振的零场分裂参量的贡献是较强的.理论计算的结果与实验值是相符的.     

Electronic and Magnetic Properties of the p-NPNN

In this paper, we study the electronic band structure and the ferromagnetic properties of the organic radical p-NPNN by employing density-functional theory with generalized gradient approximation (GGA ) and local-spin density approximation (LSDA). The density of states, the total energy, and the spin magnetic moment are calculated. The calculations reveal that the δ-phase of p-NPNN has a stable ferromagnetic ground state. It is found that an unpaired electron in this compound is localized in a single occupied molecular orbital (SOMO) constituted primarily of π^* (NO) orbitals, and the main contribution of the spin magnetic moment comes from the π^* (NO) orbitals. By comparison, we find that the GGA is more suitable to describe free radical systems than LSDA.