应材料物理与化学系祁阳教授邀请,美国内布拉斯加大学Nebraska Center for Materials and Nanoscience李兴中博士来我院访问、交流,并作学术报告,欢迎感兴趣的老师和同学参加。
报告时间:5月26日(周五)14:30
报告地点:知行楼424会议室
报告题目:Landyne - a Software Suite for Electron Diffraction Simulation and Crystallographic Analysis
报告内容简介:The Landyne software suite includes eleven stand-alone computer programs for electron diffraction simulation, data processing and crystallographic analysis. A launcher is provided so that users can conveniently access all computer programs in the software suite. The purpose of the Landyne suite is twofold: i) for use as research tools to analyze experimental results, and ii) for use as teaching tools to show students the principles of electron diffraction and crystallography. The executable codes, user manuals, specifications and a set of crystal structural data are available at http://www.unl.edu/ncmn-cfem/xzli/computer-programs. The application and main features of each computer program in the suite are briefly introduced below. More details about each computer program can be found in the user manuals and specifications.
JECP/SVAT provides a 3-D display of the crystal structure in a unit cell, including the chemical bonds and magnetic moments. The structure can be analyzed (i) as a projection in a user-selected [uvw] direction or layer-by-layer; (ii) as a local structure (or polyhedral cluster) by defining a center atom and a radius of spherical range. SPICA2e is designed for stereographic projection with applications (i) for specimen orientation using TEM holders; (ii) for generation of Kikuchi maps; (iii) for crystallographic analysis; and more. SAED3b can be used (i) to simulate selected-area electron diffraction (SAED) patterns of a single phase, twining and coexisted multiple phases with fixed orientation; (ii) to find the zone axis of the experimental diffraction pattern and indexing. PCED3b is for SAED simulation of polycrystalline phase and for phase identification. The features include (i) an integral two-beam dynamical theory for intensity calculation; (ii) out-of-plane and in-plane texture; and (iii) peak profiles of diffraction rings. JECP/HOLZ2c is an interactive program for simulation of the higher-order Laue zone (HOLZ) lines using kinematical approximation and first-order dynamic correction. JECP/QSAED2c is used to quantitatively retrieve/display the intensities of reflections in SAED patterns and precession electron diffraction (PED) patterns and to display/measure line profiles in SAED and PED patterns. QPCED2t is designed for digitization and quantification of polycrystalline SAED patterns. It can also be used to correct a pattern with elliptical rings and to enhance display for a pattern with weak diffraction rings. JECP/UCRD is used to determine the unit cell of a crystalline phase in TEM using both the reciprocal unit cell reconstruction approach and the reduced cell approach. JECP/SAKI2a is used for the simulation and analysis of Kikuchi lines and double diffraction effect in SAED patterns. Other tools are PTELS, an interactive periodic table of the elements; and TAC, a calculator for the tilting angle in TEM double-tilt and rotation holders.
JECP/SVAT provides a 3-D display of the crystal structure in a unit cell, including the chemical bonds and magnetic moments. The structure can be analyzed (i) as a projection in a user-selected [uvw] direction or layer-by-layer; (ii) as a local structure (or polyhedral cluster) by defining a center atom and a radius of spherical range. SPICA2e is designed for stereographic projection with applications (i) for specimen orientation using TEM holders; (ii) for generation of Kikuchi maps; (iii) for crystallographic analysis; and more. SAED3b can be used (i) to simulate selected-area electron diffraction (SAED) patterns of a single phase, twining and coexisted multiple phases with fixed orientation; (ii) to find the zone axis of the experimental diffraction pattern and indexing. PCED3b is for SAED simulation of polycrystalline phase and for phase identification. The features include (i) an integral two-beam dynamical theory for intensity calculation; (ii) out-of-plane and in-plane texture; and (iii) peak profiles of diffraction rings. JECP/HOLZ2c is an interactive program for simulation of the higher-order Laue zone (HOLZ) lines using kinematical approximation and first-order dynamic correction. JECP/QSAED2c is used to quantitatively retrieve/display the intensities of reflections in SAED patterns and precession electron diffraction (PED) patterns and to display/measure line profiles in SAED and PED patterns. QPCED2t is designed for digitization and quantification of polycrystalline SAED patterns. It can also be used to correct a pattern with elliptical rings and to enhance display for a pattern with weak diffraction rings. JECP/UCRD is used to determine the unit cell of a crystalline phase in TEM using both the reciprocal unit cell reconstruction approach and the reduced cell approach. JECP/SAKI2a is used for the simulation and analysis of Kikuchi lines and double diffraction effect in SAED patterns. Other tools are PTELS, an interactive periodic table of the elements; and TAC, a calculator for the tilting angle in TEM double-tilt and rotation holders.