I do not get what do you want? A crystal is one individuum and a powder contains crystals or conglomerates of crystals. Which sense SEM should have? It only images what you can see in light microscopy as well. You see what you introduced, one crystals and many particles or grains...
I think your question might be difference between SEM image of power and solid of the same compound if it is your question than answer will be no difference.
I have synthetically grown some crystals in lab. But the commercially available standard is either amorphous or semi crystalline solid. So, i want to differentiate the morphological features of both via SEM. So, any hint / published article is required which already have adopted the same strategy to assist me for text writing.
Could you tell us which phase you are investigating? A classification of a phase by its morphology (habit) might run into a trap. The most reliable characterization is still XRD. The habit can be only a hint. In your case you should not have problem with pseudomorphosis but calcite knows hundrets of different habits, and you can generate them already by minor concentrations of trace elements.
I do not know if I understand your question well. If your question was "will there be a difference between the XRD pattern of a material when it is highly crystalline and that when it is less crystalline (or amorphous)?", then following is the answer. When your materials is highly crystalline, you should get its characteristic Bragg reflections as high intensity peaks (with appropriate I/Io at correct 2theta positions) with low peak width (narrow FWHM) and with least background. The amorphous or less crystalline state of the same material may show similar peaks however with lower intensities and with broader width (large FWHM). As the degree of crystallinity goes poorer you would eventually see a flat XRD profile with huge background. If you want to identify this difference through SEM (I understand from the way the discussion goes here!), then it is not that easy. SEM can give an unreliable judgement about how much your sample is crystalline. It depend on the extent of long range ordering. Hope you got some idea from what I said.
Single crystal X-Ray diffraction is utilised for structure solution of 'phase pure' and often novel materials of unknown structure ( where micron sized or above single crystals can be grown) .
(Powder) X-Ray diffraction is utilised to in general obtain information on crystallinity and phase composition/purity of materials of often known structure where powdered material is available only. In general this methodology will not 'solve' a structure.
Happy to expand upon this if this is the information you are after by asking your original question. Not sure this question has anything to do with SEM.
A crystal is a solid in which a basic pattern, called unit cell, is repeated regularly in the three space directions. A crystal in which all the unit cells are oriented in the same way is called single crystal. In the single crystal X-ray crystallography, diffraction measurements are perfomed using single crystals to determine the crystal structure. If single crystals are of too small dimensions to be analyzed individually, we talk about powder. For diffraction study, an amount of powder is needed. In the powder lattices are randomly oriented, and one speaks, in this case, of the Powder X-ray diffraction (PXRD).
In both cases X-rays are absorbed and scattered by the crystal. As the crystals spread the X-rays only in certain preferred directions, the phenomenon is called X-ray diffraction (XRD) instead of X-ray diffusion.
In sum, XRD is general, while single crystal X-ray crystallography only involves single crystals.