The vector correlations between products and reagents for the title reactions have been calculated by the quasi-classical trajectory method at a collision energy of 21.32 kJ/mol on an accurate potential energy surface...The vector correlations between products and reagents for the title reactions have been calculated by the quasi-classical trajectory method at a collision energy of 21.32 kJ/mol on an accurate potential energy surface of Ho et al. （J. Chem. Phys. 119, 3063 （2003））. The peaks of the product angular distribution are found to be in both backward and forward directions for the two title reactions. The product rotational angular momentum is not only aligned, but also oriented along the negative direction of y-axis. These theoretical results are in good agreement with recent experimental findings for the two title reactions. The isotopic effect is also revealed and primarily attributed to the difference of the mass factor in the two title reactions.展开更多
The quasi-classical trajectory calculations O＋＋DH（v=0,j=0）→OD＋＋H reactions on the RODRIGO potential energy surface have been carried out to study the isotope effect on stereo-dynamics at the collision energies ...The quasi-classical trajectory calculations O＋＋DH（v=0,j=0）→OD＋＋H reactions on the RODRIGO potential energy surface have been carried out to study the isotope effect on stereo-dynamics at the collision energies of 1.0, 1.5, 2.0, and 2.5 eV. The distributions of dihedral angle P（~r） and the distributions of P（Or） are discussed. Furthermore, the angular distributions of the product rotational vectors in the form of polar plot in θr and φr are calculated. The differential cross section shows interesting phenomenon that the reaction is dominated by the direct reaction mechanism. Reaction probability and reaction cross section are also calculated. The calculations indicate that the stereo-dynamics properties of the title reactions are sensitive to the collision energy.展开更多
High-entropy alloys(HEAs)contain multiple principal alloying elements,but usually with simple crystal structures.Quasicrystals are structurally complex phases,but are generally dominated by only one element.However,ne...High-entropy alloys(HEAs)contain multiple principal alloying elements,but usually with simple crystal structures.Quasicrystals are structurally complex phases,but are generally dominated by only one element.However,nearequiatomic high-entropy quasicrystals have rarely been reported because they are difficult to prepare experimentally and predict theoretically.Therefore,the preparation and crystal structures of near-equiatomic high-entropy quasicrystals have drawn much interest.We report a quinary decagonal quasicrystal(DQC)with near-equiatomic alloying elements in Al20Si20Mn20Fe20Ga20 melt-spun ribbons,which is the first to our knowledge.Meanwhile,the structural features of the DQC are characterized in detail.The configurational entropy of both the alloy and DQC satisfies the entropy-based criterion for HEAs,suggesting a high-entropy DQC.Our findings provide a new strategy to develop high-entropy quasicrystals.展开更多
基金ACKNOWLEDGMENTS The authors thank Prof. Ke-li Han for providing stereodynamics QCT code, and thank Dr. T. S. Ho and Prof. H. Rabitz for providing the potential energy surface. This work is supported by the National Natural Science Foundation of China （No.10947103）, the Foundation for Outstanding Young Scientist in Shandong Province （No.2008BS01017）, and the Young Fhnding of Jining University （No.2009QNKJ02）.
文摘The vector correlations between products and reagents for the title reactions have been calculated by the quasi-classical trajectory method at a collision energy of 21.32 kJ/mol on an accurate potential energy surface of Ho et al. （J. Chem. Phys. 119, 3063 （2003））. The peaks of the product angular distribution are found to be in both backward and forward directions for the two title reactions. The product rotational angular momentum is not only aligned, but also oriented along the negative direction of y-axis. These theoretical results are in good agreement with recent experimental findings for the two title reactions. The isotopic effect is also revealed and primarily attributed to the difference of the mass factor in the two title reactions.
文摘The quasi-classical trajectory calculations O＋＋DH（v=0,j=0）→OD＋＋H reactions on the RODRIGO potential energy surface have been carried out to study the isotope effect on stereo-dynamics at the collision energies of 1.0, 1.5, 2.0, and 2.5 eV. The distributions of dihedral angle P（~r） and the distributions of P（Or） are discussed. Furthermore, the angular distributions of the product rotational vectors in the form of polar plot in θr and φr are calculated. The differential cross section shows interesting phenomenon that the reaction is dominated by the direct reaction mechanism. Reaction probability and reaction cross section are also calculated. The calculations indicate that the stereo-dynamics properties of the title reactions are sensitive to the collision energy.
基金the National Natural Science Foundation of China(51871015 and 51471024)the Selfdetermined Project of the State Key Laboratory for Advanced Metals and Materials(2016Z-13)。
文摘High-entropy alloys(HEAs)contain multiple principal alloying elements,but usually with simple crystal structures.Quasicrystals are structurally complex phases,but are generally dominated by only one element.However,nearequiatomic high-entropy quasicrystals have rarely been reported because they are difficult to prepare experimentally and predict theoretically.Therefore,the preparation and crystal structures of near-equiatomic high-entropy quasicrystals have drawn much interest.We report a quinary decagonal quasicrystal(DQC)with near-equiatomic alloying elements in Al20Si20Mn20Fe20Ga20 melt-spun ribbons,which is the first to our knowledge.Meanwhile,the structural features of the DQC are characterized in detail.The configurational entropy of both the alloy and DQC satisfies the entropy-based criterion for HEAs,suggesting a high-entropy DQC.Our findings provide a new strategy to develop high-entropy quasicrystals.
