| 查看: 5065 | 回復(fù): 16 | |||
[求助]
為什么我的GSAS精修Rp Rwp如此的小呢?
|
|||
|
大家好!我用GSAS精修粉末XRD得到的Rp=0.5%,Rwp=0.63%,chi2=0.1444;為什么我Rp和Rwp的值比別人的小一個(gè)數(shù)量級(jí)呢?(順便問一下 GSAS liveplot中的wRp是不是就是Rwp呢?)大牛們精修的值不可能比我小啊,精修的圖形也還行啊見附圖(說明一下,圖中扣除了一些非晶背底)請大俠賜教為什么? 部分精修圖 |
GSAS結(jié)構(gòu)精修 |
至尊木蟲 (著名寫手)
至尊木蟲 (著名寫手)
|
If the background has been subtracted, yi(obs) is the net intensity after subtraction, but if the background is refined, yi(obs) [and yi(calc)] is likely to include the background contribution. In the latter case, a high background will automatically produce a low Rwp value, because a significant part of the intensity is accounted for by the background function. Thus, the comparison of profile R values from different kinds of powder diffraction experiments can be extremely misleading. For example, Rwp for neutron TOF data are often quite small (e.g. a few %), while those for laboratory X-ray data are larger (e.g. ~10%). 從這段話里可以知道你的Rwp為什么那么低的原因是你背底很高 |
鐵桿木蟲 (知名作家)
![]() |
|
木蟲 (小有名氣)
至尊木蟲 (著名寫手)
|
你這個(gè)太小了0.144,你看看下面文獻(xiàn)的說明,希望對你有幫助。 J. Appl. Cryst. (1999). 32, 36-50 chi2 is also quoted quite often in the literature, should approach 1. If the data have been `over-collected' (i.e. errors are no longer dominated by counting statistics), Rexp will be very small and chi2 for a fully refinned structure much larger than 1. Conversely, if the data have been `under-collected' (i.e. collected too quickly), Rexp will be large and chi2 could be less than 1. Strange chi2 values can also arise from data for which the e.s.d.'s of the counts have been incorrectly calculated (e.g. counts given as counts per second are assumed to be the absolute counts). |
| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 材料求調(diào)劑一志愿哈工大324 +6 | 閆旭東 2026-03-28 | 7/350 |
|
|---|---|---|---|---|
|
[考研] 266求調(diào)劑 +11 | 陽陽哇塞 2026-03-27 | 12/600 |
|
|
[考研] 266分求材料化工冶金礦業(yè)等專業(yè)的調(diào)劑 +4 | 哇呼哼呼哼 2026-03-26 | 4/200 |
|
|
[考研] 269專碩求調(diào)劑 +10 | 金恩貝 2026-03-21 | 10/500 |
|
|
[考研] 一志愿北京化工大學(xué)材料與化工 264分各科過A區(qū)國家線 +10 | 哈哈157349 2026-03-21 | 10/500 |
|
|
[考研] 316求調(diào)劑 +5 | 江辭666 2026-03-26 | 5/250 |
|
|
[考研] 071000生物學(xué)求調(diào)劑,初試成績343 +6 | 小小甜面團(tuán) 2026-03-25 | 6/300 |
|
|
[考研] 281求調(diào)劑 +3 | 亞克西good 2026-03-26 | 5/250 |
|
|
[考研] 085601求調(diào)劑總分293英一數(shù)二 +4 | 鋼鐵大炮 2026-03-24 | 4/200 |
|
|
[考研] 299求調(diào)劑 +4 | 15188958825 2026-03-25 | 4/200 |
|
|
[考研] 07化學(xué)303求調(diào)劑 +5 | 睿08 2026-03-25 | 5/250 |
|
|
[考研] 材料與化工328分調(diào)劑 +6 | 。,。,。,。i 2026-03-23 | 6/300 |
|
|
[考研] 0854AI CV方向招收調(diào)劑 +4 | 章小魚567 2026-03-23 | 4/200 |
|
|
[考研] 300分,材料,求調(diào)劑,英一數(shù)二 +5 | 超贊的 2026-03-24 | 5/250 |
|
|
[考研] 求調(diào)劑一志愿武漢理工大學(xué)材料工程(085601) +5 | WW.' 2026-03-23 | 7/350 |
|
|
[考研] 277分求調(diào)劑,跨調(diào)材料 +3 | 考研調(diào)劑lxh 2026-03-24 | 3/150 |
|
|
[考研] 一志愿國科過程所081700,274求調(diào)劑 +3 | 三水研0水立方 2026-03-23 | 3/150 |
|
|
[考研] 269求調(diào)劑 +4 | 我想讀研11 2026-03-23 | 4/200 |
|
|
[考研] 一志愿南大,0703化學(xué),分?jǐn)?shù)336,求調(diào)劑 +3 | 收到VS 2026-03-21 | 3/150 |
|
|
[考研] 336求調(diào)劑 +5 | rmc8866 2026-03-21 | 5/250 |
|