Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On X-ray scattering model for single particles, Part I: The legacy of
  protein crystallography   Emerging coherent X-ray scattering patterns of single particles have shown
dominant morphological signatures in agreement with predictions of the
scattering model used for conventional protein crystallography. The key
question is if and to what extent these scattering patterns contain volumetric
information, and what model can retrieve it. The scattering model of protein
crystallography is valid for very small crystals or those like crystalized
biomolecules with small coherent subunits. But in the general case, it fails to
model the integrated intensities of diffraction spots, and cannot even find the
size of the crystal. The more rigorous and less employed alternative is a
purely-classical crystal-specific model, which bypasses the fundamental notion
of bulk and hence the non-classical X-ray scattering from bulk. This
contribution is Part 1 out of two reports, in which we seek to clarify the
assumptions of some different regimes and models of X-ray scattering and their
implications for single particle imaging. In this part, first basic concepts
and existing models are briefly reviewed. Then the predictions of the
conventional and the rigorous models for emerging scattering patterns of
protein nanocrystals (intermediate case between conventional crystals and
single particles) are contrasted, and the terminology conflict regarding
"Diffraction Theory" is addressed. With a clearer picture of crystal
scattering, Part 2 will focus on additional concepts, limitations, correction
schemes, and alternative models relevant to single particles. Aside from such
optical details, protein crystallography is an advanced tool of analytical
chemistry and not a self-contained optical imaging technique (despite
significant instrumental role of optical data). As such, its final results can
be neither confirmed nor rejected on mere optical grounds; i.e., no
jurisdiction for optics.

16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex