According to feather element tree, the base level and basecoordinatesystem are created, then we can choose them when we need them at any time.
根据特征元素树创建了基准面和基准坐标系，使我们很方便的在需要参照基准的时候来选取它。
2
Base on the crystal-field theory, all of the crystal-field potentials of 32point-group are given for family iron ions and the relationships of which with different coordinate-system are studied.