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1.
在单双迭代包括非迭代三重激发微扰处理的耦合簇CCSD(T)理论水平下,采用aug-ccPVQZ并加上键函数(3s3p2d2f1g)组成的大基组,计算得到了体系在冻结HCN键长情况下的全程势能面.计算结果表明该势能面存在2个势阱:较深的势阱对应于线性Ne-HCN构型,阱深为61.56cm-1,其中Rm=8.00a0;较浅的势阱对应于T型构型,其中Rm=6.62a0,θ=102°,阱深为52.48cm-1,整个势能面呈现出弱的各向异性.  相似文献   

2.
He-LiH势能面的ab initio计算   总被引:6,自引:5,他引:1  
采用超分子耦合簇理论CCSD(T)方法和由键函数3s3p2d1f组成的大基组,计算得到了He-LiH体系在冻结LiH键长情况下的全程势能面.该势能面存在2个势阱,较深的势阱对应于线性He-LiH构型,其中Rm为4.25a0,阱深为177.53cm-1 ,较浅的势阱对应于线性He-HLi构型,其中Rm为9.875a0,阱深仅为9.90cm-1,整个势能面表现强的各向异性.  相似文献   

3.
采用aug-cc-pVQZ(弥散函数的基组)/Na、aug-cc-pVDZ(弥散函数的基组)/Ne以及中点键函数的大基组,使用单、双迭代并包含三重激发微扰校正的耦合簇CCSD(T)理论方法,计算了NeNa2基态146个基态单点能.通过拟合96个参数,给出了NeNa2三原子分子体系的基态分子势能函数的解析表达式,并分析了其基态二维势能面的特性,在此基础上绘出了NeNa2三原子分子体系的三维势能曲线.计算结果表明,NeNa2基态势能面存在2个较浅的势阱,对应于=80,R_NeNa=33a0处,势阱的阱深约为-675010-1cm-1和线型结构=0,R_NeNa=10a0处,势阱深度约为-234110-3cm-1.此三原子分子体系的势能面呈现出弱的角度各向异性.  相似文献   

4.
采用超分子耦合簇理论CCSD(T)方法和由键函数3s3p2d组成的大基组,计算得到了范德华体系C3-Ar在C3分子处于线性平衡构型时的全程分子间势能面.该势能面存在2个相等的极小值,分别为θ=75.5°,Rm=0.379nm,θ=104.5°,Rm=0.379nm,Vm=156.234cm-1,整个势能面表现强的各向异性.采用离散变量表象和Lanczos方法计算得到了C3-Ar体系的振动能级,计算结果表明,C3-Ar的CCSD(T)势能面支持64个振动束缚态.  相似文献   

5.
以超冷分子的感应冷却实验为背景,研究同核碱金属双原子分子Li2和F原子体系在低和超低碰撞能条件下的冷碰撞动力学机理.针对弱相互作用势能面构建出一个精确势能函数,使势能函数既能考虑到以排斥占优的短程相互作用也能兼顾到以吸引为主的长程相互作用.计算结果表明,Li2—F基态势能面存在2个比较浅的势阱,θ=0°对应于倒"T"型结构,RLi—Li=5.6a0时,阱的深度约为-0.18 cm-1;θ=90°对应于线型结构,RLi—Li=2a0时,阱的深度约为-0.23 cm-1.Li2—F分子体系整个势能面呈现出了强的角度各向异性.  相似文献   

6.
采用CCSD(T)方法和aug-cc-pVQZ-PP/aug-cc-pVQZ基函数,计算得到了Xe-HF体系解析表达的势能面,发现该势能面有两个势阱,分别位于线性构型Xe-H-F和Xe-F-H,阱深分别为-290.61cm-1和-120.2cm-1.  相似文献   

7.
运用CCSD(T)理论,采用aug-cc-pVTZ基组对PD2分子的基态结构进行了优化和频率计算.得到的平衡核间距RPD=0.142 36 nm,键角∠DPD=91.806 9°,离解能De(DP-D)=3.407 0 eV,对称伸缩振动频率v1(a1)=1 709.376 0 cm-1,弯曲振动频率v2(a1)=806.839 9 cm-1和反对称伸缩振动频率v3(b2)=1 718.941 1 cm-1.用多体项展式理论导出基态PD2分子的解析势能函数,该势能表面准确地再现了PD2分子的平衡结构特征.  相似文献   

8.
Kr-Xe体系势能曲线和光谱研究   总被引:1,自引:1,他引:0  
采用超分子耦合簇 CCSD(T)方法和有效核势aug-cc-PVXZ-PP(X=T,Q,5)基组,计算了Kr-Xe体系的相互作用势,并分别采用三种方案外推得到基底限值.不同基底和外推方法,势能曲线平衡位置在7.991-8.025a0,阱深在-158.42-153.24cm-1,计算了Kr-Xe体系振转能级和各同位素基振动态的纯转动跃迁频率,及相应的光谱常数,并与实验结果进行了比较.  相似文献   

9.
用原子分子反应静力学原理推导出了Hinx(x=0、+1)分子离子的基态电子状态及其离解极限.在LANL2DZ水平基础上,用B3LYP方法计算了Hinx(x=0、+1)分子离子的基态电子状态的平衡几何Re和离解能De分别为Hin0.185 9 nm、2.789 6 eV;Hin+0.177 9 nm、2.789 2 eV,并在计算出来的一系列单点势能基础上,用正规方程组拟合Murrell-Sorbie(M-S)势能函数,得到相应态的解析势能函数,由此计算对应的光谱参数(Be、αe、ωe、ωeχe),计算结果分别为Hin4.919 3 cm-1、0.102 9 cm-1、1 390.657 8 cm-1和22.318 0 cm-1; Hin+5.013 1 cm-1、0.210 1 cm-1、158 606 328 cm-1和2 504 520 cm-1,计算值与实验和文献值基本一致,计算表明Hinx(x=0、+1)分子离子是可稳定存在的,其稳定性次序为Hin>Hin+.  相似文献   

10.
为了弄清BCl在金属蚀刻中的机理,了解BCl分子激发态势能函数和稳定性的基本信息是必要的.运用群论及原子分子反应静力学方法,推导出了BCl分子低激发态A1Π、a3Π1的电子态及相应的离解极限;使用SAC/SAC—CI方法,6-311 g(d)**基组对BCl分子低激发态A1Π、a3Π1的平衡结构和谐振频率进行了几何优化计算,并对BCl分子低激发态A1Π、a3Π1进行了单点能扫描计算,用正规方程组拟合Murrell—Sorbie函数,得到相应电子态的势能函数解析式,利用得到的势能函数计算了相对应的力常数(f2、f3、f4)和光谱数据(Be、αe、ωe、ωeχe),数据值分别为:基态BCI(X1Σ )的Re=0.1867 nm,De=1.4855 eV,Be=0.6228 cm-1,αe=0.0060 cm-1,ωe=810.2001 cm-1,ωeχe=4.981 cm-1;激发态BCI(a3Π1)的Re=0.1726 cm,De=6.1151 eV,Be=0.6843 cm-1,αe=0.0039 cm-1,ωe=897.8493 cm-1,ωeχe=5.2800 cm-1;激发态BCI(A1Π)的Re=0.1722 nm,De=7.1515 eV,Be=0.6799cm-1,αe=0.0085 cm-1,ωe=784.5359 cm-1,ωeχe=12.88 cm-1.结果与文献数据相符合;在基态的平衡位置处,计算了从基态到A1Π、a3Π1态的垂直激发能,其值分别为7.6291 eV,10.1023 eV.  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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