Z =8. The X-ray diffraction intensity data were collected on a four-circle diffractometer. The strueture has been solved by direct method and refined by block-diagonal least squares method. The final R wag 0.075 for 3146 independent observed reflexions.

• Z=8.；用四圆衍射仪收集X射线衍射强度数据；用直接法解晶体结构；用块对角矩阵最小二乘法进行结构修正；参与修正的可观测独立反射点共3146个