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1.
3He4He与H2分子碰撞的同位素效应研究   总被引:1,自引:1,他引:0       下载免费PDF全文
用公认精确度较高的密耦近似方法计算了入射能量E=0.5eV时惰性气体原子3He(4He)与H2分子替代碰撞体系的转动激发碰撞截面.通过分析3He(4He)-H2碰撞体系分波截面和微分截面的差异,总结出在氦原子的同位素替代情形下3He(4He)-H2碰撞体系分波截面和微分截面随分波数增加和同位素原子质量改变的变化规律.  相似文献   

2.
基于Huxley势函数的拟合势,通过精确度较高的密耦近似方法计算了入射能量为50meV和150meV时,氦原子的四种同位素3He,4He,9He,10He与HCl分子碰撞体系的激发分波截面.通过分析不同能量下,各碰撞体系分波截面的差异,探讨了不同入射能量时He的同位素对He-HCl碰撞体系的分波截面的影响,总结出其分波截面随量子数和体系约化质量的变化规律.  相似文献   

3.
基于Hux1ey势函数的拟合势,通过精确度较高的密耦近似方法计算了入射能量为50 meV和150meV时,氦原子的四种同位素3He,4He,9He,10He与HCl分子碰撞体系的激发分波截面.通过分析不同能量下,各碰撞体系分波截面的差异,探讨了不同入射能量时He的同位素对He-HCl碰撞体系的分波截面的影响,总结出其分波截面随量子数和体系约化质量的变化规律.  相似文献   

4.
用Tang-Toennies势模型和密耦近似方法计算了不同能量下惰性气体原子He与H2及其同位素D2,T2替代碰撞体系的振转激发碰撞截面. 通过分析He-H2(D2,T2)各碰撞体系分波截面的差异,总结出在H2分子的对称同位素替代情形下He-H2(D2,T2)碰撞体系分波截面随量子数和体系 关键词: 散射截面 密耦方法 同位素  相似文献   

5.
用公认精确度较高的密耦近似方法计算了入射能量E=05eV时惰性气体原子3He(4He)与H2分子替代碰撞体系的转动激发碰撞截面.通过分析3He(4He)-H2碰撞体系分波截面和微分截面的差异,总结出在氦原子的同位素替代情形下3He(4He)-H2碰撞体系分波截面和微分截面随分波数增加和同位素原子质量改变的变化规律. 关键词: 散射截面 密耦方法 同位素替代 散射角  相似文献   

6.
低能氖原子与H2(D2、T2)分子碰撞微分截面的研究   总被引:6,自引:0,他引:6  
用密耦方法及Tang-Toennies势模型计算了Ne-H2(D2、T2)碰撞体系的转动激发碰撞截面,得到了H2分子的对称同位素替代情形下Ne-H2(D2、T2)三碰撞体系总截面及微分截面的变化规律.  相似文献   

7.
氦同位素与氢分子碰撞的振转激发分波截面研究   总被引:1,自引:0,他引:1       下载免费PDF全文
用密耦近似方法和Tang-Toennies势模型计算了E=0·7eV时,氦原子的四种同位素3He,4He,9He,10He与氢分子H2碰撞体系的振转激发分波截面.通过分析各碰撞体系分波截面的差异,探讨了He(3He,4He,9He,10He)-H2碰撞体系的弹性碰撞、纯转动激发和振转激发情况下,其分波截面随量子数和体系约化质量的变化规律.  相似文献   

8.
当入射氦原子能量E=0.2 eV时,用密耦方法计算了He-H2(D2,T2)碰撞的微分散射截面.  相似文献   

9.
用Tang-Toennies势模型和密耦近似方法计算了不同能量下惰性气体原子He与H2及其同位素D2,T2替代碰撞体系的振转激发碰撞截面. 通过分析He-H2(D2,T2)各碰撞体系分波截面的差异,总结出在H2分子的对称同位素替代情形下He-H2(D2,T2)碰撞体系分波截面随量子数和体系  相似文献   

10.
用多体刚性椭球模型计算了不同能量下氦的同位素原子4He,10He与钠的同位素分子18Na2,23Na2,37Na2 替代碰撞体系的转动激发积分散射截面.通过分析4He,10He-18Na2,23Na2,37Na2各转动激发积分散射截面的差异,总结出在钠分子的对称同位素替代情形下4He,10He -18Na2,23Na2,37Na2碰撞体系转动激发积分散射截面随钠分子转动量子数和体系约化质量变化的规律.结果表明,体系的约化质量及入射原子相对碰撞能量的变化均给体系的碰撞截面带来不同程度的影响.另外,计算了相对入射能量为100 meV时,相互作用势的不同区域对10He-18Na2,23Na2,37Na2各碰撞体系转动激发积分散射截面的贡献情况. 关键词: 多体刚性椭球模型 转动激发积分散射截面 钠同位素分子 椭球等势面  相似文献   

11.
Neutron diffraction study of polycrystalline HoRu2Si2, HoRh2Si2, TbRh2Si2, and TbIr2Si2 was performed in the temperature range between 4.2 and 300 K. For HoRu2Si2 the magnetic spin alignment of a linear transverse wave mode below the Néel temperature 19 K is observed. This static moment wave is propagating along the b-axis with k=(0, 0.2, 0) and is polarized in the c-axis. The root-mean-square and maximum saturation moments per Ho atom are 9.26 and 13.09μB, respectively. HoRh2Si2, TbRh2Si2 an TbIr2Si2 are simple collinear antiferromagnets of +-+- type with Néel temperatures of (27±1), (98±2) and (72±3) K, respectively. For TbRh2Si2 and TbIr2Si2 magnetic moments are localized on RE ions only and are aligned along the tetragonal axis, while for HoRh2Si2 they form an angle ø = (28±3)°.  相似文献   

12.
Muon spin relaxation experiments have been carried out in the paramagnetic and magnetically ordered states of URh2Si2 and CeRh2Si2. As the magnetic structure of these compounds is well known, these measurements can help to characterise their magnetic properties probed by μSR and to understand the μSR results of the heavy fermion compounds of the same crystallographic family. Our measurements show that the muons occupy two different crystallographic sites. The spectra of URh2Si2 and CeRh2Si2 in the magnetically ordered states are very different, probably reflecting their different magnetic structures. The spectra obtained on CeRh2Si2 are similar to the published spectra of the heavy fermion compound CeCu2.1 Si2. Muon spin rotation measurements on LaNi2As2 indicate that the muon is diffusing at 150 K.  相似文献   

13.
14.
The CO2 TEA laser irradiation of CBr2F2 in the presence of Cl2 yielded 13C-enriched CBrClF2 and 13C-enriched CCl2F2 under selected experimental conditions. As the photolysis proceeded, the 13C concentration of CBrClF2 decreased gradually and that of CCl2F2 increased up to 90% or higher. These results can be explained by the mechanism involving the secondary 13C-selective IRMPD of the primary product CBrClF2. On the other hand, the carbon-containing product for a CCl2F2/Br2 system was only CBrClF2; the further IRMPD of which probably regenerated CBrClF2 in the presence of Br2. The decomposition probabilities of 12C- and 13C-containing molecules in both systems were measured as functions of laser line, laser fluence, and reactant pressures.  相似文献   

15.
16.
正Since the discovery of superconductivity in LaFeAsO_(1-x)F_x,the high-T_c iron-based superconductors have been extensively studied from both experimental and theoretical viewpoints [1-8]. However, the mechanism of the unconventional superconductivity is still to be resolved. To  相似文献   

17.
Far infrared (30–430 cm?1) reflectivity measurements of Hg2Cl2 and Hg2Br2 single crystals have been performed in polarized light. The spectra, which are in agreement with group-theoretical predictions, were analyzed by the oscillator fitting procedure and Kramers-Kronig method. The results are compared with the existing data from other measurements and the large anisotropy of polar modes is briefly discussed. The polarization vectors of all long-wavelength symmetry modes were determined group-theoretically.  相似文献   

18.
Longitudinal and transverse magnetostrictions of polycrystalline samples of intermetallic compounds RMn2Ge2 (R=Sm or Gd) are measured in pulsed magnetic fields up to 250 kOe. It is found that linear magnetostrictive strains of about 10?3 arise in a temperature range in which the magnetic field causes a change in the magnetic state of a manganese magnetic subsystem. The results obtained are described within the model of a two-sublattice ferrimagnet with a negative exchange interaction in the manganese subsystem in terms of a strong dependence of this interaction on interatomic distances.  相似文献   

19.
Both pseudobinary systems exhibit large homogeneous regions of cubic and hexagonal Laves phases. Ordering tendencies on crystallographic sites between Al and the transition metals are observed in the hexagonal type.Electron transfer to the transition metals quenches their moments so that they become nonmagnetic at high Al concentrations. The peculiarities in the mechanism of magnetization which appear in rare earth dialuminides when Al is replaced by a transition metal have been studied in detail at cryogenic temperatures.The first replacement of Al results in a decrease in saturation moment. Neutron diffraction verifies the low ordered rare earth sublattice moments and reveals the ‘lost part’ as a disordered component. Considerable magnetic hardness develops in certain regions of concentration often connected with spontaneous increases in magnetization with field. All available evidence suggests the presence of unusual domain wall effects to be responsible for this effect. High remanences develop in both the hexagonal and in the cubic structures in the intermediate region. The development of disordered magnetic components is connected either with the disorder on crystallographic sites or changes in the free electron concentration.  相似文献   

20.
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