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I published a number of crystal structures using a powerful X ray diffractor and high quality crystals where H density was both found and modeled. Modeling H de
by muaytimbo 4y ago
I published a number of crystal structures using a powerful X ray diffractor and high quality crystals where H density was both found and modeled. Modeling H density in and of itself is in no way a sign of fake data, it is just a rare occurrence.
- verisimi 4y agoHang on, isn't a model by necessity not the same as the thing it's modeling? Obviously a photo is sort of a model, but depending on what the subject is, you can visually verify it. If it's a software model, and say you enter lots of parameters, I have to wonder how valid that model is.. How can it be verified?
- ta988 4y agoThe way you solve x-ray diffraction structures is that you refine your model until the electron density matches.
- verisimi 4y agoThanks.. But until your electron density matches what?
- muaytimbo 4y agoYou change the position and identity of the atoms in your model until there is very little residual electron density left remaining.
- verisimi 4y agoThese are words, but I don't see how they prove the model. I guess it's like some sort of check after the operation is complete? Why does a low residual electron density prove the model? What is electron density anyway? And how do we measure it?
- muaytimbo 4y agoYes humans communicate using "words". Nothing is ever "proven" in science since there is always an arbitrarily complex hypothesis than can explain captured data. Instead, the weight of evidence is considered. Anyway it seems like this whole conversation is out of your depth currently. There are many good X-ray crystallography texts available if your interest continues.
- opticfluorine 4y agoSure. But in this case there was no claim of a sufficiently strong X-ray source for this, so it fell flat on its face.
- muaytimbo 4y agoThe X-ray I used was "in house". The OP didn't mention what the X-ray source used was so the absence of mentioning "sufficiently strong" isn't proof.