Cheng Y Q, Ramirez-Cuesta A J
Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
J Chem Theory Comput. 2020 Aug 11;16(8):5212-5217. doi: 10.1021/acs.jctc.0c00569. Epub 2020 Jul 31.
The thermal neutron scattering cross-section of a solid depends on the energy (or wavelength) of the incident neutrons. Devising a method to calculate the energy dependence from first principles, without the approximations built in the scattering theory, has been a major undertaking in nuclear engineering. Here, we demonstrate such a calculation method using the program OCLIMAX. Our approach eliminates various approximations and limitations involved in a regular calculation with the LEAPR module of NJOY code, and the results are compared with available experimental and theoretical data. It is also demonstrated how additional insight can be obtained from the calculated full dynamical structure factor. The results reported here show the great potential and excellent platform provided by OCLIMAX for future development in the study of neutron thermalization in solid materials for different applications.
固体的热中子散射截面取决于入射中子的能量(或波长)。设计一种从第一原理计算能量依赖性的方法,而不采用散射理论中固有的近似方法,一直是核工程领域的一项主要工作。在此,我们使用OCLIMAX程序演示了这样一种计算方法。我们的方法消除了使用NJOY代码的LEAPR模块进行常规计算时涉及的各种近似和限制,并将结果与现有的实验和理论数据进行了比较。还展示了如何从计算得到的完整动态结构因子中获得更多的见解。此处报告的结果表明,OCLIMAX为固体材料中不同应用的中子热化研究的未来发展提供了巨大潜力和出色平台。