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21.
1991MRSubjectClassification82DRecentlythere11asbeenaconsiderableinterestinthestudyofthelatticeintegrable1llodelswithopenBC[1--4].Inarecelltpapel['],acompletelistofintegrablenineteen-vertexluodelswaspresellted.Thelistcolilprisesseveralwell--knowllmodels[6]andfournewoiles.The1'0firnewonesweresolvedbyKlulllpcr[7].alldtheBCforthenewoileswerestudio(lillRef.[8].Illthepresentpaper,wewillstlldytheBCforanothertwomodelsillthelist,whichillcludethe0liesinRef.Ig-10]respectively.BysolvingtheRE,three…  相似文献   
22.
C20F20分子电子输运性质的第一性原理研究   总被引:4,自引:0,他引:4       下载免费PDF全文
利用第一性原理密度泛函理论和非平衡格林函数方法研究了C20F20分子的电子输运性质. 计算得到了C20F20分子的平衡电导为0385 G0 其I-V曲线表现出较好的线性特性. 在有限偏压范围内具有较稳定的电导值, 可以用于制备稳恒电阻分子器件. 关键词: 20F20分子')" href="#">C20F20分子 电子输运 分子器件  相似文献   
23.
近几年来 ,人们用李代数方法处理了许多问题 [1~ 5] ,在此基础上 ,我们利用动力学李代数方法研究了准线型四原子分子高激发振动态 ,把分子的 Hamiltonian展开成 Casimir算子与 Majorana算子之和[6,7] ,然后进行代数处理 ,从而得到了代数 Hamiltonian的本征值 .1 基本理论四原子分子有 3个键 ,所满足的对称群为 G=U1(4) U2 (4) U3 (4) ,处理分子问题时 ,一般要考Fig.1  The bond coordinates of fulminic acid(HCNO)虑键与键之间的耦合 ,为了方便 ,首先让键 1与键 2耦合 ,然后再与键 3耦合 (图 1 ) .这种耦合方式可记为 (1 2 ) 3 …  相似文献   
24.
Wave packet propagation techniques are used to find experimentally reliable laser parameters that yield optimal production.The photoionization and photodissociation dynamics of sodium iodine molecules are interpreted into several channels.Several frequencies are found to be suitable for NaI molecules during the photoionization and dissociation processes.Photon-dressed excited states and electron-dressed ionic continuum states facilitate the search for available laser parameters.  相似文献   
25.
A full-dimensional analytical potential energy surface(APES) for the F + CH4 →HF + CH3 reaction is developed based on 7127 ab initio energy points at the unrestricted coupled-cluster with single,double,and perturbative triple excitations.The correlation-consistent polarized triple-split valence basis set is used.The APES is represented with a many-body expansion containing 239 parameters determined by the least square fitting method.The two-body terms of the APES are fitted by potential energy curves with multi-reference configuration interaction,which can describe the diatomic molecules(CH,H2,HF,and CF) accurately.It is found that the APES can reproduce the geometry and vibrational frequencies of the saddle point better than those available in the literature.The rate constants based on the present APES support the experimental results of Moore et al.[Int.J.Chem.Kin.26,813(1994)].The analytical first-order derivation of energy is also provided,making the present APES convenient and efficient for investigating the title reaction with quasiclassical trajectory calculations.  相似文献   
26.
The potential energy curves (PECs) of the 3Π states of GaX (X=F, Cl, and Br) molecules are calculated using the multireference configuration interaction method with a large contracted basis set aug-cc-pV5Z. The PECs are accurately fitted to analytical potential energy functions (APEFs) using the Murrell–Sorbie potential function. The spectroscopic parameters for the states are determined using the obtained APEFs, and compared with the theoretical and experimental data available presently in the literature.  相似文献   
27.
安义鹏  杨传路  王美山  马晓光  王德华 《中国物理 B》2010,19(11):113404-113404
Using density functional theory and quantum transport calculations based on nonequilibum Green’s function formalism,we investigate the charge transport properties of endohedral M@C 20 (M=Na and K) metallofullerenes.Our results show that the conductance of C 20 fullerene can be obviously improved by insertion of alkali atom at its centre.Both linear and nonlinear sections are found on the I-V curves of the Au-M@C 20-Au two-probe systems.The novel negative differential resistance behaviour is also observed in Na@C 20 molecule but not in K@C 20.  相似文献   
28.
Employing the quasi-classical trajectory method and the potential energy surface of Panda and Sathyamurhy [Panda A N and Sathyamurthy N 2004 J.Chem.Phys.121 9343],the effect of the reagent vibration on vector correlation of the ion-molecule reactions D~-+H2 and H~-+D2 is studied at a collision energy of 35.7 kcal/mol.Four generalized polarization-dependent differential cross sections (2π/σ)(dσ 00 /dωt),(2π/σ)(dσ 20 /dωt),(2π/σ)(dσ 22+ /dωt),and (2π/σ)(dσ 21 /dωt) are presented in the centre-of-mass reference frame,separately.At the same time,the effects on the product angular distributions P (θr),P (φr) and P (θr,φr) of the title reactions are also analysed.The calculated results show that the scattering tendencies of the product HD,the alignment and the orientation of j sensitively depend on reagent molecule vibration.  相似文献   
29.
分别用PW91,B3LYP两种密度泛函方法和全电子高斯基组对β-Si3N4的几何结构进行全优化(包括晶格参数和原子坐标),结果和实验值符合良好. 同时计算了能带结构和态密度. 在此基础上分别用上述两种方法计算了Γ点拉曼振动频率,并按对称性进行分类,将得到的11种拉曼活性模式的频率值与实验值以及其他文献值进行了比较,进一步确定了Ag模式为中等频率,值约459cm-1. 计算结果表明,B3LYP总体计算结果优于PW91. 对于中低频段的拉曼频率,两者与实验值相差最大为2和17cm-1. 对于高频段,两者与实验值相差最大为16和35cm-1. 同时计算了β-Si3N4的Γ点红外振动频率,通过对比实验结果,将其红外光谱进行了归属.  相似文献   
30.
本文采用准经典轨线方法,在LEPS势基础上计算了Ca+CH3I→CaI+CH3在不同碰撞能下的矢量相关计算了质心系中四个广义极化微分反应截面(2π/σ)(dσ00/dωt),(2π/σ)(dσ20/dωt),(2π/σ)(dσ22+/dωt),(2π/σ)(dσ21-/dωt),k-j′两矢量相关的P(θr)分布、k-k′-j′三矢量相关的极角分布P(φr)以及用θr和φr表示的产物转动角动量的空间分布P(θr,φr).  相似文献   
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