这是本文档旧的修订版!
得到的脚本如下:
# ------------------------------------------------------------- # Bulk Configuration # ------------------------------------------------------------- # Set up lattice lattice = FaceCenteredCubic(5.4306*Angstrom) # Define elements elements = [Silicon, Silicon] # Define coordinates fractional_coordinates = [[ 0. , 0. , 0. ], [ 0.25, 0.25, 0.25]] # Set up configuration bulk_configuration = BulkConfiguration( bravais_lattice=lattice, elements=elements, fractional_coordinates=fractional_coordinates ) # ------------------------------------------------------------- # Calculator # ------------------------------------------------------------- #---------------------------------------- # Basis Set #---------------------------------------- basis_set = [ GGABasis.Silicon_DoubleZetaPolarized, ] #---------------------------------------- # Exchange-Correlation #---------------------------------------- exchange_correlation = GGA.PBE numerical_accuracy_parameters = NumericalAccuracyParameters( k_point_sampling=(7, 7, 7), ) calculator = LCAOCalculator( basis_set=basis_set, exchange_correlation=exchange_correlation, numerical_accuracy_parameters=numerical_accuracy_parameters, ) bulk_configuration.setCalculator(calculator) nlprint(bulk_configuration) bulk_configuration.update() nlsave('Silicon (alpha).nc', bulk_configuration) # ------------------------------------------------------------- # Bandstructure # ------------------------------------------------------------- bandstructure = Bandstructure( configuration=bulk_configuration, route=['G', 'X', 'W', 'L', 'G', 'K', 'X', 'U', 'W', 'K', 'L'], points_per_segment=20, bands_above_fermi_level=All ) nlsave('Silicon (alpha).nc', bandstructure)
将脚本发送到 Job Manager 执行,稍等片刻即可在主窗口中的LabFloor中看到计算结果(选定输出的nc文件)。
VNL提供了方便的能带分析工具(主窗口右侧Band Structure Analyzer),可以直接作图、查看能带结构,并在能带上进行交互式测量。所得能带结构也可以导出数据和图像。同时,可以在这些高对称方向上进行有效质量分析。 ===== 关于高对称点 ===== VNL中默认的高对称点的标志依赖于晶格的布拉维格子种类,在Builder中 * 可以通过Crystal Symmetry Info查看体系的对称性; * 使用 Brillouin Zone Viewer 查看这些高对称点在布里渊区里的位置; * 如果发现体系的格子属性不对,导致无法设置需要的高对称点,则可以在Lattice Parameters…**里调整格子,也有可能需要重新优化结构;