USER-MESONT is a LAMMPS package for simulation of nanomechanics of carbon 
nanotubes (CNTs). The model is based on a coarse-grained representation 
of CNTs as "flexible cylinders" consisting of a variable number of 
segments. Internal interactions within a CNT and the van der Waals 
interaction between the tubes are described by a mesoscopic force 
field designed and parameterized based on the results of atomic-level 
molecular dynamics simulations. The description of the force field 
is provided in the papers listed below.

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This package was created by Maxim Shugaev (mvs9t@virginia.edu) 
at the University of Virginia.
The Fortran library implementing basic level functions describing stretching, 
bending, and intertube components of the mesoscopic CNT force field, used
by this package is developed by Alexey N. Volkov (avolkov1@ua.edu) 
at the University of Alabama.

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The following commands are contained in this package:

atom_style mesont
  This command enables mesont atom_style containing variables used for 
  further commands in USER-MESONT.

pair_style mesont/tpm cut table_path BendingMode TPMType 
  This command activates a pair_style describing CNT mesoscopic tubular 
  potential model (TPM) force field. "cut" is cutoff distance that should 
  be set to be at least max(2.0*L, sqrt(L^2/2 + (2.0*R + Tcut)^2)), 
  where L is the maximum segment length, R is the maximum tube radius, 
  and Tcut = 10.2 A is the maximum distance between surfaces of interacting 
  segments. However, the recommended cutoff is 3L.

compute mesont
  This command allows evaluation of per atom and total values of stretching, 
  bending, and intertube interaction components of energies. Use the following 
  flags: 'estretch', 'ebend', 'etube'.

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References:

L. V. Zhigilei, C. Wei, and D. Srivastava, Mesoscopic model for dynamic 
simulations of carbon nanotubes, Phys. Rev. B 71, 165417, 2005.

A. N. Volkov and L. V. Zhigilei, Structural stability of carbon nanotube 
films: The role of bending buckling, ACS Nano 4, 6187-6195, 2010.

A. N. Volkov, K. R. Simov, and L. V. Zhigilei, Mesoscopic model for simulation 
of CNT-based materials, Proceedings of the ASME International Mechanical 
Engineering Congress and Exposition (IMECE2008), ASME paper IMECE2008-68021, 
2008.

A. N. Volkov and L. V. Zhigilei, Mesoscopic interaction potential for carbon 
nanotubes of arbitrary length and orientation, J. Phys. Chem. C 114, 5513-5531, 
2010.

B. K. Wittmaack, A. H. Banna, A. N. Volkov, L. V. Zhigilei, Mesoscopic 
modeling of structural self-organization of carbon nanotubes into vertically 
aligned networks of nanotube bundles, Carbon 130, 69-86, 2018.

B. K. Wittmaack, A. N. Volkov, L. V. Zhigilei, Mesoscopic modeling of the 
uniaxial compression and recovery of vertically aligned carbon nanotube 
forests, Compos. Sci. Technol. 166, 66-85, 2018.

B. K. Wittmaack, A. N. Volkov, L. V. Zhigilei, Phase transformation as the 
mechanism of mechanical deformation of vertically aligned carbon nanotube 
arrays: Insights from mesoscopic modeling, Carbon 143, 587-597, 2019.

A. N. Volkov and L. V. Zhigilei, Scaling laws and mesoscopic modeling of 
thermal conductivity in carbon nanotube materials, Phys. Rev. Lett. 104, 
215902, 2010.

A. N. Volkov, T. Shiga, D. Nicholson, J. Shiomi, and L. V. Zhigilei, Effect 
of bending buckling of carbon nanotubes on thermal conductivity of carbon 
nanotube materials, J. Appl. Phys. 111, 053501, 2012.

A. N. Volkov and L. V. Zhigilei, Heat conduction in carbon nanotube materials: 
Strong effect of intrinsic thermal conductivity of carbon nanotubes, Appl. 
Phys. Lett. 101, 043113, 2012.

W. M. Jacobs, D. A. Nicholson, H. Zemer, A. N. Volkov, and L. V. Zhigilei, 
Acoustic energy dissipation and thermalization in carbon nanotubes: Atomistic 
modeling and mesoscopic description, Phys. Rev. B 86, 165414, 2012.

A. N. Volkov and A. H. Banna, Mesoscopic computational model of covalent 
cross-links and mechanisms of load transfer in cross-linked carbon nanotube 
films with continuous networks of bundles, Comp. Mater. Sci. 176, 109410, 2020.
