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41.
Influence of the reagent vibration on the stereo-dynamics of the reactions D^- + H2 and H^- + D2 下载免费PDF全文
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
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Ab initio investigations of the charge transport properties of endohedral M@C20(M=Na and K)metallofullerenes 下载免费PDF全文
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
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推导了用对比参数表示的平衡蒸汽压力方程和平衡蒸汽密度方程,这些方程适用于D2在临界点以下的行为,计算表明,用对比状态计算露点温度下的蒸汽密度比露点法准确,用BWR方程计算充气压力比用理想气体方程合理。 相似文献
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Electronic Structure of One—Dimensional Boron Chains with Density Functional Theory Method 下载免费PDF全文
One-dimensional chain structures of Bn(n=6-16) are calculated by employing a 6-311 G^* basis set.The present calculations show that all the chain structures of interest have local minima with large binding energy per atom and short bond length.It is also found that many previous reported structures of B6 and B7 clusters are saddle points and the one-dimensional chain structures are the corresponding ground-state structures of B6 and B7 clusters. 相似文献
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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
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Potential energy curve study on the ^3Π electronic states of GaX (X=F,Cl, and Br) molecules 下载免费PDF全文
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
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Dynamic mechanism for encapsulating two HIV replication inhibitor peptides with carbon nanotubes 下载免费PDF全文
Encapsulation of biomolecules inside a carbon nanotube(CNT) has attracted great interest because it could enable the delivery of nanoscale pharmaceutical drugs with CNT-based devices.Using a molecular dynamics simulation,we investigate the dynamic process by which human immunodeficiency virus(HIV) replication inhibitor peptides(HRIPs) are encapsulated in a water solution contained inside a CNT.The van der Waals attraction between the HRIPs and the CNT and the root-mean-square deviation are used to analyse the evolution of the encapsulation.It is found that the interaction between the HRIPs and the CNT is the main driving force for the encapsulation process,which does not cause an obvious conformational change to the HRIPs. 相似文献