Here you can find atomic configurations of carbon fibers and computer codes used in the structural analysis of these configurations, as described in this paper:
Kaushik Joshi, Mikhail I. Arefev, and Leonid V. Zhigilei
"Generation and characterization of carbon fiber microstructure in atomistic simulations," Carbon 152, 396408, 2019, PDF, doi:10.1016/j.carbon.2019.06.014.
The table below gives several examples of the structural analysis of carbon canfigurations. By clicking on links above you can download data files defining the structure of one of the carbon fiber (CF) samples, a small graphene flake, and the results of the structural analysis of these two systems  files with coordinates of ring centers, voids, and graphene regions, as well as structure factor calculated for powder diffraction case, distribution of carbon ring orientations, and identification of nonsixmember carbon rings. 
Atomic configurations (input)  Output of the structural analysis codes  
Computational sample Structure 4 (2.9 Mb) 
Coordinates of graphene rings (1.1 Mb) 
Structure factor for isotropic (powder) diffraction (11 Kb) 
Coordinates of points on void surfaces (132 Kb) 
Orientation of carbon rings (1 Kb) 

Identification of graphitic regions (2.9 Mb) 
StoneWales defect in graphene (2 Kb) 
The format of the files is as follows: (1) For *.xyz microstructure files, the total number of atoms is given in the first line, the dimensions of the system in x, y, and z directions are given in the second line. The atomic types and x, y, z coordinates are listed in all of the remaining lines. (2) For ring center *.xyz file, the first line is a number of rings. All other lines contain information about individual rings: the number of atoms in the ring (see README file of the corresponding code), as well as x, y and z coordinates. (3) For void *.xyz file, the first line is a number of points on void surfaces defining the voids. All other lines list type of a point on the void surface, which should be "S", as well as x, y and z coordinates of the point. (4) For XRD *.data file, the first colum is the normalized structure factor, the second column is 2θ in degrees. (5) For the ring orientation *.data file, the first column is cosine of an angle α with respect to the fiber axis and the second column is a percentage of rings with this angle. The methods used for the structural characterization of atomic configurations are described in the paper listed above. More information on the file format can be found in ReadMe files of the codes available under the links below. 
You can download the source codes for structural analysis and structure factor
calculations (with examples of input and output) by following these links: Source code for structural analysis of carbon fibers (by Kaushik Joshi) Source code for structure factor calculations (by Mikhail Arefev)
A brief description of the codes is provided in the User Manual 
Structure 1 (L1_L2_na.xyz) 
Structure 2 (L1_L2_xa.xyz) 
Structure 3 (L3_L4_L5_xa.xyz) 
Structure 4 (L4_L5_xa.xyz) 
Structure 5 (L4_L5_xyza.xyz) 
The data is produced, and the codes are developed with support from the U.S. Department of Energy,
Office of Energy Efficiency and Renewable Energy,
Vehicle Technologies Program,
Award Number DEEE0008195. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the U.S. Department of Energy.
