| 查看: 1075 | 回复: 3 | ||
| 当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖 | ||
[求助]
请高手根据编辑意见帮我精修一下单晶吧，先谢谢啦
|
||
我是新手，编辑给的意见好多，我完全不知道该怎么下手啦 而且我也没有SHELXTL软件。帮帮忙吧，需要什么文件请跟我说，现在我是一头雾水了。 以下是编辑意见：（好长啊，头晕  ）1. The "_diffrn_measured_fraction_theta_full" is too low. I note you have cut off your reflection file at theta = 25.1 deg yet your unit cell determination uses reflections up to theta = 27.69 deg. I include a quote from CheckCIF relative to this point: " Ideally (and a requirement for publication in Acta Crystallographica), this fraction should be close to 1.0 for theta-full greater or equal to sin(theta/lambda) = 0.6 (i.e. 25.24 degrees for MoKa and 67.7 degrees for CuKa radiation). The three major causes of incomplete data sets are: 1 - A missing cusp of data due to data collection by rotation around the spindle axis only (standard on some image-plate systems). Cure: collect an additional data set after remounting the crystal. 2 - The DENZO imageprocessing package has problems with certain strong reflections. They are often excluded from the data set. Cure: Add an additional scan at lower power setting in order to include strong low order reflections. 3 - Incomplete scans, possibly based on erroneously assumed higher than actual symmetry." Thus your theta(max) cutoff is too low and this may be part of the problem. I am also puzzled by the small number of reflections collected. Did you collect a full sphere of data? With an APEX-II that shouldn't take an inordinate amount of time. If your present data set doesn't have enough measurable data so that you can get "_diffrn_measured_fraction_theta_full" above 0.99 at theta = 25.24 deg, it will be necessary to recollect the data using longer scan times and/or at low temperature. 2. It appears that the reflection 1 0 0 is obscured by the beamstop and should be omitted from the final refinement. 3. Please be certain that your final weighting scheme is correct (I get different values than you report in my test refinement). 4. Your Fig. 2 needs to be redrawn using circles or only the outlines of the ellipsoids, not full ellipsoids, and should include those H-atoms which are involved in the H-bonding. Also, the O2-H2...O3 interaction has too small an angle to be considered a true H-bond. |
回复此楼» 猜你喜欢
中南大学化学化工学院易小艺教授课题组招收2026级博士研究生（第二轮）
已经有0人回复
-
求助
已经有1人回复
-
无机化学论文润色/翻译怎么收费?
已经有67人回复
-
0703化学26考研调剂，一志愿南昌大学
已经有2人回复
-
有没有化学、材料专业的同学需要调剂 考虑天津高效的可以邮件或者私信
已经有1人回复
-
26年博士招生
已经有15人回复
-
江西理工大学功能晶态材料方向刘遂军课题组招收2026年秋季入学博士研究生
已经有10人回复
-
宁夏大学团簇新材料团队招收材料/化学/化工专业博士生
已经有0人回复
-
MIL-101有单晶样品吗
已经有0人回复
-
西北大学26年化学博士招生
已经有2人回复
» 本主题相关价值贴推荐，对您同样有帮助:
- 求高手精修下一个单晶结构
已经有4人回复
- 请高手指点一下，一个加氢键精修的问题，软件加氢键后运行不了
已经有15人回复
- 请教Rietveld精修的一般步骤与参数设置？
已经有12人回复
- 40金悬赏解决一个孪晶问题，单晶结构精修。。。。
已经有7人回复
- 请教一下配合物单晶如何精修，用什么软件精修。怎么精修，不是本专业，非常谢谢
已经有3人回复
- 求高手精修晶体并得到氢键表，本人非此专业。烦请高手求解
已经有9人回复
- 初学者请各位高手帮忙看一下GSAS精修的结果，请指点
已经有14人回复
- 【交流】求教XRD高手帮忙看看这幅图XRD解构精修图是怎么弄的
已经有10人回复
- 【请教】请教GSAS精修问题
已经有14人回复
4楼2011-11-03 09:48:53
2楼2011-11-02 20:39:16
3楼2011-11-03 08:55:01
