what the XRD software used to indexing of unknown compound?. I prepared anew transition metal complex and i want to deduce the structure of its whether cubic or tetragonal or hexagonal etc... What is the XRD software used for this purpose?
Your question is already incorrect. Indexing and structure is not related to each other. The indexing is based on the crystal lattice which exclusively describes the translation symmetry. The crystal lattice defines, where a peak appears. The lattice is invariant, i.e. you can describe it by different definitions of basis vectors, but as in algebra this does not change the available vectors but only their "names", i.e. their indexing. From this follows that phases with the same lattice (parameters) will have the same peak positions. Whether you are seeing a peak or not, i.e. the intensity of an interference, however, depends on the atiomic distribution (crystal structure). Since lattice and structure have different impact it is important to use them correctly! This is a big problem in material science since structure and lattice are mixed. There are even many people using redicules terms like "lattice structure" :-|.
Coming back to your question: first you have to index the peaks, i.e. you need a software which is able to find a crystal lattice (the translation-symmetric arrangement of MATHEMATICAL points, i.e. NO atoms!) which fits to all interferences hkl (or vectors in reciprocal space). If this is clear, you can start to determine the atomic distribution within the unit cell. The symmetry of the lattice cannot be lower than the symmetry of the structure (but vice versa which is called pseudo-symmetry). Since in powder diffraction all lattice points with the same distance (Bragg angle) are displayed by the same reflection you cannot use it for structure determination since all (perhaps) independent reflections are overlaped. For this you can only use single crystal techniques which enable the investigation of each reciprocal lattice point. However, if you have a very good model of your structure (sommonly from a very similar phase), and you only need to refine this model, you can apply the so-called Rietveld technique. Of course, this only works for non-complicated materials since you need clearly more well-extractable interferences than parameters defined by your crystal structure, i.e. coordinates of your atoms and several further unknown parameters like occupation and substitution factors, parameters of your instrument etc.
An indexing software every well-equiped diffractometer should have. Of course, there are free-available indexing softwares available. A good place to search for such software is www.ccp14.ac.uk. Rietveld-related software is also free-available, but summarizing I have to warn you that there is no software which you simply can apply. It needs at least a few months experience to become familiar with all required settings and understand, what the software is doing. And this is a general requirement: you can save time if you use an unfamiliar software, but you need to understand entirely what this software is doing. All these packages will generate some numbers, but they are not reliable as long as you don't know exactly how the applied software extracts them. The structure determination field is too complicated in order to generate a code which is running automatically with the same success for any problem (phase, symmetry, etc). Thanks to all these fantastic guys we have access to their software, but we still have to think by ourself! You also don't switch on a transmission electron microscope and expect you will have a reliable and correctly interpretable image in a few seconds only because it is claimed by their manufacturers it is user friendly. It will perhaps show you something, but as long as you do not understand to set-up a TEM correctly all images are useless.
The structure was solved by direct methods using SHELXS86 [33] and refined on F2 for all reflections using SHELX93 [34].
[33] G.M. Sheldrick, Acta Cryst. 46A (1990) 467–473.
[34] G.M. Sheldrick, SHELXL93: Program for Structure Refinement; University of
Göttingen, Göttingen, 1993.
There are two things mixed up: First, for crystal cell detn, use powder-XRD and solve it with TREOR. If you want the structure of the TM-complex, then you have to grow a single crystal and ask for a single Xtal XRD. The hkl data is treated with SHELX suit. Is this what you asked for?
Dear Abass!
May be you have solved the question by now as it is already lot of days after I am attempting to answer your question however I suppose you want to check your crystal structure rather than solving a structure if it is so then ur structure can be checked using Cambridge crystallographic data centre CCDC or scifinder if you do not have access to these databases please let me know so that I can try.
I hope I could understand your question and my reply was any helpful
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