For a rapid screening of potentially interesting inorganic phases, one may need automated lower cost single crystal X-ray diffractometers instead of (or better in addition to) "traditional" equipment that guarantee higher accuracy, but require much more manpower for the sample preparation. Desktop diffractometers are around for some years now and would be glad to receive some feedback. Are they really fully automated? Do you really save time (and money)? Would it be worth it to buy one, having a traditional single crystal diffractometer already at hand in our lab?
Piero, I might be wrong but all desktop diffractometers are (meant) for powders. For powders I haev seen patterns collected on the bruker and Rigaku and the quantitative phase analyisis is exactly the same you get from a more pricey solution. Not sure you can do routine structural solution or line profile analysis, but IMHO for routine powder work the gap between benchtop and larger brother is quite narrow
Piero, I might be wrong but all desktop diffractometers are (meant) for powders. For powders I haev seen patterns collected on the bruker and Rigaku and the quantitative phase analyisis is exactly the same you get from a more pricey solution. Not sure you can do routine structural solution or line profile analysis, but IMHO for routine powder work the gap between benchtop and larger brother is quite narrow
Dear all, thanks for your answers. I am also interested to have an idea about powder diffractometers, but my question was related to single crystal ones. To my knowledge there are two such kind of machines, from Bruker (SMARTX 2S) and from rigaku (XTAL Lab mini). Perhaps other companies produce similar items but I am not aware. So I am asking if anybody has experience with one of these machines and could recommend them.
We use desktop diffractometers built around Teltron tubes to teach our first-year undergraduate students about single-crystal and powder diffraction. There are some details about the experiments we perform in the students' handout, beginning on page 21:
http://www.msm.cam.ac.uk/teaching/partIA/courseA/IA-courseA-practicalbook.pdf
Generally, it is not the diffractometer that needs to be updated but the method of recording and analyzing XRD data that needs a revolutionary change. I notice that the XRD manufacturers are still peddling century old technology and techniques on recently manufactured high precision diffractometers. I've used diffractometers ranging from those deemed "dinosaurs" (GE Diano from the 1950's with a Philips X-ray Generator) during the 1980's as well as the more recent (2010) updated Panalytical X'Pert/MRD system. I find it scandalous that XRD professionals are not yet acquiring the entire 2D diffractogram (reciprocal space image). Instead, we are continuing to use the age old 0D conventional point counter and convoluting data from a large sampling area into a single "blind" data point while neglecting the rich 2D XRD data in most cases. Somehow, through complicated mathematical manipulations we are still able to extract meaningful Nano structural parameters from this convoluted "mess" we create.
I've used desk-top diffractometers (Diano, Bruker, Rigaku, Panalytical & Bede) for analyzing powders, mono-crystals, poly-crystals, para-crystals, fibers, foils, epitaxial films, substrates, amorphous materials, composites, etc..
It is possible to turn any diffractometer in to a powerful XRD Microscope using a real time 2D XRD Imaging devise. The precision of the "dinosaur" Diano was as good as any modern diffractometer. What will make the big difference is a high frame rate, high spatial resolution, high dynamic range, high gain (sensitivity), 2D detector. In general the size (25mm to 250mm) of the detector would be inversely proportional to its spatial resolution (5-200um presently). As the spatial resolution of the 2D detector improves XRD Microscopy could rival any of the other high resolution microscopy methods such as TEM without all the "sample prep" and without the vacuum. There is even the possibility of creating additional magnification using "divergent beam" & "glancing angle" techniques.
Matteo! You are never wrong. The last time I thought you were wrong was when I was mistaken. Now on, I have no choice but to agree with you even before I read your comments.
"patterns collected on the Bruker and Rigaku and the quantitative phase analyisis is exactly the same you get from a more pricey solution", I agree! In fact, the instrument is irrelevant. It is the resolution of the data collected that is critical. The results should all be identical if the Nano structure of the sample is unchanged. Accounting for the variations in the wavelength dispersion and the angular divergence for the instrument optics correctly should always yield identical answers.
Piero! "Bruker (SMARTX 2S) and from Rigaku (XTAL Lab mini)" - What detector system do these come with? What detector system do you employ for your "single crystal" work? I was fortunate to see the Bruker instrumentation in use at NYU recently. Check out this LinkedIn discussion and see if you could glean off any helpful details: http://www.linkedin.com/groupItem?view=&gid=2683600&type=member&item=171615833&trk=groups_search_item_list-0-b-ttl&goback=%2Egna_2683600
If I'm not mistaken again, Rigaku uses the curved flat panel detector to conduct the single crystal work in 2D. What is the approximate cost of that system?
You may find some helpful information in this discussion as well:
http://www.linkedin.com/groupItem?view=&gid=2683600&type=member&item=260221141&trk=groups_search_item_list-0-b-ttl&goback=%2Egna_2683600
- Badges
- Science method
- Similar topics
- Methodology
- Crystallography
- X-ray Diffraction