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1.
使用相对论的和非相对论的赝势在HF,MP2,CCSD和CCSD(T)水平上计算了M2Te(M=Cu,Ag,Au)的平衡几何和振动频率.计算的结果表明,这些化合物的基态(单态),弯曲结构是稳定的,线性结构是不稳定的.在MP2水平上研究了电子相关对这些化合物的几何结构的修正.电子相关对键角的修正是非常明显的,对于M=Cu,Ag,Au,角∠M-Te-M分别减少了23.3°,21.8°和21.8°.电子相关对键长的修正是微小的.相对论效应轻微地缩短了Au2Te的键长.比较这三个化合物,Au2Te相对稳定.  相似文献   

2.
M2As-和M2Br+(M=Cu,Ag,Au)的赝势从头算研究   总被引:1,自引:1,他引:0  
使用赝势在HF和MP2水平上计算了M2As-和M2Br+(M=Cu,Ag,Au)的平均几何和振动频率。计算的结果表明,这些化合物呈弯曲结构(C2v)。在MP2水平上研究了电子相关对这些化合物的几何结构的修正,键角减少10°到20°。在MP2,MP3,MP4,CCSD,和CCSD(T)水平上还较详细地研究了电子相关对Au2As-的几何结构的修正。通过对这些化合物稳定性的研究,预言了Au2As-的成键可能性。  相似文献   

3.
使用相对论和非相对论赝势,在HF和MP2理论水平上详细研究了电子相关效应和相对论效应对含重金属铜、银和金的二聚物(M2Te)2,(M=Au,Ag,Cu)的几何构型和稳定性的影响.结果显示,电子相关效应缩短二聚物的金属-金属键长和金属-碲键长、提高振动频率、降低能量,使二聚物的结构变得较为刚性和紧凑;相对论效应加强了它的强度,使二聚物更加稳定.?  相似文献   

4.
使用相对论和非相对论赝势,在HF和MP2理论水平上研究了重金属混合/掺杂团簇(M2Te)3(M=Au, Ag, Cu) 的几何构型和稳定性.结果显示,团簇存在具有D3h,C2v和C3v对称性的三种稳定异构体,并且各异构体之间能量相差很小.电子相关效应对M-M键长的修正十分显著,而对M-Te键长和Te-M-Te键角的修正非常小.相对论效应使所有键长变短、Te-M-Te键角变大.两种效应都提高振动频率、降低能量,使团簇结构变得更加紧凑,使多聚物趋于更加稳定.  相似文献   

5.
在不同电子相关水平上基于相对论和非相对论赝势,对含重金属硅化物SiM(M=Au,Ag,Cu)的基态几何结构和光谱特性进行了研究,并讨论了电子相关效应和相对论效应的影响.结果表明:重金属硅化物SiM(M=Au,Ag,Cu)的基态电子状态是2Π.电子相关效应缩短了金属硅化物的键长,提高了分离能,谐振频率也增加,使SiM(M=Au,Ag,Cu)的结构变得更加紧凑,基态更加稳定.相对论效应加强了它的强度,使三种硅化物更加稳定.相对论作用的顺序为AuSi>AgSi>CuSi.  相似文献   

6.
在重金属铜、银和金的团簇中电子相关作用的定量估算   总被引:8,自引:4,他引:4  
在HF和CCSD(T)水平上研究了重金属碲化物团簇M2Te(M=Cu,Ag,Au)的电子相关作用.结果显示,电子相关作用不改变键长,却减小键角大于20°,说明电子相关作用是作用在重金属原子上的一种切向吸引力.理论分析确定,这个吸引力来自于重金属闭壳层d10-d10之间的van der Waals吸引力.通过拟合电子相关势能函数 ,首次估算了电子相关作用的大小和作用模式.  相似文献   

7.
在HF和CCSD水平上研究了重金属钋化物团簇M2Po(M=Cu,Ag,Au)中电子相关效应.结果显示,电子相关效应改变键角大约16°,但几乎不改变键长,说明电子相关效应是作用在重金属原子上的一种切向吸引力.理论分析确定,这个吸引力来自于重金属闭壳层d10~d10之间的van der Wals吸引力.采用一个较简单的经典模型拟合了电子相关势能函数,并估算了它的大小和作用模式.  相似文献   

8.
根据原子与分子反应静力学和群论理论推导出二元合金小团簇M2Ga(M=Cu,Ag,Au)的离解极限和基态电子态.采用量子力学从头算方法及小核实赝势和相应的基组,对二元合金小团簇M2Ga进行几何优化,得到M2Ga基态(2B2)为弯曲平面型结构,并与单元团簇M3(M=Cu,Ag,Au)相似.计算得到合金团簇比单元团簇稳定,其中Au2Ga体系最稳定.同时给出谐振频率、力常数,并且分析得到电子相关效应使得团簇更加紧凑、稳定性增强.  相似文献   

9.
利用相对论小核赝势研究了重金属钋化物分子MPo(X2∏),(M=Cu,Ag,Au).用群论方法结合原子分子反应静力学原理导出了分子的基电子状态和相应的离解极限,并在各种电子相关理论水平上计算了它们的平衡几何和振动频率.在此基础上用Murrell-Sorbie函数形式拟和势能曲线,得到了总的解析势能函数,并计算出了光谱数据和力常数.  相似文献   

10.
采用密度泛函理论的B3LYP和PBE1PBE方法,对IB金属小团簇与C2H3自由基间的相互作用进行了研究.结果发现:C2H3M0/-n(M=Cu、Ag、Au;n=1-3)最稳定及其异构体的结构都相同,只是键长、键角有所不同.在C2H3M0/-n(M=Cu、Ag、Au;n=1-3)的最稳定结构中,C2H3自由基和金属团簇都作为整体单元存在.由于金属团簇与C2H3自由基的相互作用,在红外吸收光谱中,C2H3自由基中C=C、C-H键的伸缩振动发生了红移,而随着团簇中金属原子数目的增多,C=C键及C-H键的伸缩振动,红移程度减小.基于含时密度泛函(TDDFT)计算,模拟了C2H3M-n(M=Cu、Ag、Au;n=1-3)最稳定结构的光电子能谱(PES).  相似文献   

11.
S. Suchat  K. Paithoonwattanakij 《Optik》2010,121(21):1944-1947
We propose an interesting scheme on photon states generation using a fiber optic Mach Zehnder interferometer incorporating a fiber optic ring resonator without any optical pumping parts including in the system, which is available for long-distance link. In principle, the state of a quantum bit, it is known, unknown, or entangled to other systems. The desired quantum states are generated and transmitted in the link via a fiber optic. The transmission quality in terms of quantum fidelity is analyzed, where a high fidelity to the noiseless quantum channel is achieved by adding an ancillary photon after the signal photon within the correlation time of the fiber noise and by performing the quantum parity checking method. The error correction is also analyzed. For simplicity, feature and robustness against path-length mismatches among the nodes make our scheme suitable for multi-user quantum communication networks.  相似文献   

12.
以Breit-Pauli哈密顿的球张量形式为基础,借助不可约张量理论,在拉卡表象下计算了类铝体系基态能量相对论修正(包括相对论质量修正项、单体和双体达尔文修正项、自旋-自旋接触和轨道-轨道相互作用项)。在此基础上,引入了一个与核电荷数Z相关的能量修正项,用以弥补因忽略能量的其它高阶项对原子体系能量的影响。计算结果与实验值非常接近。  相似文献   

13.
在类氢离子电子束缚能一级相对论修正的基础上,计算了原子核的体积效应及质量效应对较轻元素及同位素类氢离子能级的修正量,结果显示,原子核的体积及质量效应不仅导致同位异核氢及类氢离子精细结构能级出现分裂,还会导致类氢离子精细结构能级的简并消失。  相似文献   

14.
Enhanced radiative corrections generated in SUSY extensions of the Standard Model spoil the fit of the precision data (Z-boson decay parameters and W-boson mass). This negative effect is washed out for heavy enough squarks, because of the decoupling property of SUSY models. We find that even for light squarks the enhanced radiative corrections can be small. In this case substantial mixing is necessary.  相似文献   

15.
An estimate is presented of the leading radiative corrections to low energy electroweak precision measurements from strong nonresonant WW scattering at the TeV energy scale. The estimate is based on a novel representation of nonresonant scattering in terms of the exchange of an effective scalar propagator with simple poles in the complex energy plane. The resulting corrections have the form of the corrections from the standard model Higgs boson with the mass set to the unitarity scale for strong WW scattering.  相似文献   

16.
It is shown that non-rotating black holes in three or four dimensions possess a canonical entropy. Recently study indicated that there were logarithmic corrections to Bekenstein–Hawking entropy in area with a uncertain coefficient which depends on specific models. In this paper, the thermal fluctuations on Bekenstein–Hawking entropy in five-dimensional topological AdS (TAds)-black holes and topological de Sitter (Tds) spaces will be considered based on a uniformly spaced area spectrum approach.  相似文献   

17.
In this work,we study the effects of the Weyl corrections on the p-wave superfluid phase transition in terms of an EinsteinMaxwell theory coupled to a complex vector field.In the probe limit,it is observed that the phase structure is significantly modified owing to the presence of the higher order Weyl corrections.The latter,in general,facilitates the emergence of the superfluid phase as the condensate increases with the Weyl coupling measured byγ.Moreover,several features about the phase structure of the holographic superfluid are carefully investigated.In a specific region,the phase transition from the normal phase to the superfluid phase is identified to be the first order,instead of being the second order,as in the cases for many holographic superconductors.By carrying out a numerical scan of model parameters,the boundary dividing these two types of transitions is located and shown to be rather sensitive to the strength of Weyl coupling.Also,a feature known as"Cave of Winds",associated with the emergence of a second superfluid phase,is observed for specific choices of model parameters.However,it becomes less prominent and eventually disappears asγincreases.Furthermore,for temperature in the vicinity of the critical one for vanishing superfluid velocity,denoted by T0,the supercurrent is found to be independent of the Weyl coupling.The calculated ratio,of the condensate with vanishing superfluid velocity to that with maximal superfluid velocity,is in good agreement with that predicted by Ginzburg-Landau theory.While compared with the impact on the phase structure owing to the higher curvature corrections,the findings in our present study demonstrate entirely different characteristics.Further implications are discussed.  相似文献   

18.
We present complete next-to-leading-order (NLO) QCD correction and electro-weak (EW) correction to the production cross section of Higgs-Boson in association with two hard quark jets by using Monte-Carlo numerical calculation program, HAWK, for various photon parton distribution functions at the Large Hadron Collider with center of mass energy 7, 8, 13, and 14 TeV without and with typical vector-Boson-fusion cuts on the tagging jets. In our calculation we include complete contribution from the full set of t-channel, u-channel and s-channel Feynman diagrams, and corresponding interferences as well as NLO QCD and EW corrections.  相似文献   

19.
多电子原子能量的相对论修正   总被引:3,自引:1,他引:2  
以Breit-Pauli哈密顿的球张量形式为基础,借助不可约张量理论,建立了计算多电子原子能量的相对论修正的一种解析理论形式,导出了多电子原子相对论修正项(包括相对论质量修正项、单体和双体达尔文修正项、自旋-自旋接触相互作用项和轨道-轨道相互作用项)在斯莱特表象中的矩阵元的解析表达式,完成了所有角向积分和自旋求和计算.利用所建立的理论,对类锂体系(1s)2(2p)2P态能量的相对论修正进行了具体计算.  相似文献   

20.
We consider the effects of quark masses to the perturbative thrust in e + e annihilation. In particular we show that perturbative power corrections resulting from non-zero quark masses considerably alters the size of the non-perturbative power corrections and consequently, significantly changes the fitted value of αs.  相似文献   

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