SHELXS解析比SHELXT快案例1

DJ_Tokyo

SHELXS解析比SHELXT快案例1

文本所用软件/程序

GUI: Olex2[1]    Space group determination: XPREP[2]    Structure solution: SHELXS[3],  SHELXT[4]    Structure refinement: SHELXL[5]

案例来源：CCDC[6] 2382497, DOI[7]:10.5517/ccdc.csd.cc2kz5rh.

案例结构式如图1所示。

▲图1 案例结构

XPREP确定其空间群为第14号中心对称空间群P21/c，如图2所示。

▲图2 XPREP确定的空间群

在Olex2中Work>>Solve下Program中选择ShelXS作为解析程序，Method中选择Direct Methods[8]作为解析方法，随后点击Solve按钮进行结构解析，几乎是秒解（0.1秒，解析起止时间均为08:20:29），解析得到的Q峰可以直接看出结构框架，如图3所示，只需对照图1结构将框架中的Q峰指认为相应原子即可。

▲图3 SHELXS直接法解析结果

而使用SHELXT进行解析，耗时14.801秒，解析结果为比P21/c空间群对称性更低的第7号非中心对称空间群Pc，非对称单元ASU（asymmetry unit）中有两个分子，虽然程序指认了结构，但指认的结构残缺不全，如图4所示。

▲图4 SHELXT解析结果

SHELXT解析结果后续需要进行升空间群操作使空间群更正为P21/c，不论采用上述哪种解析方案，最终解析精修结果如图5所示。

▲图5 最终结果

视频操作演示请参阅：

单晶结构解析练习175(数据还原)：https://www.bilibili.com/video/BV13KpYetEGt

如需数据进行练习，请从以下链接下载：

链接:https://pan.baidu.com/s/1kTwCCiNiMbI4J9l-GXozTQ

提取码: q47p

参考文献

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