Build module

The mode is used to build carbon and boron nitride structures from scratch and print the xyz structures to a file.

The program can create the following structures:

  • Carbon nanotubes ((n, m) CNTs) and boron nitride nanotubes of arbitrary length and radius in zigzag and armchair conformations.

  • Walls of arbitrary size in the x and y directions. Multiple layers can be constructed in ABA stacking.

  • The CNTs and carbon walls can be combined to form a ‘pore’ structure, either as an open tube with walls on both sides or with the tube closed off on one side and a wall on the other side.

  • All structures are designed to satisfy periodic boundary conditions wherever possible.

  • Structures can be functionalized using user-defined groups.

Wall Wall_N wall_side CNT Pore Pore_closed

This mode is started with the -c flag.

$ CONAN -c

Once the mode is started, a console opens that takes in commands to build the structures:

###########################################
##                                       ##
##   #####  #####  #   #  #####  #   #   ##
##   #      #   #  ##  #  #   #  ##  #   ##
##   #      #   #  # # #  #####  # # #   ##
##   #      #   #  #  ##  #   #  #  ##   ##
##   #####  #####  #   #  #   #  #   #   ##
##                                       ##
###########################################

CONAN-build:

It is recommended to use VMD(Visual Molecular Dynamics) in conjunction with the the build-tool. If VMD is installed it can be started using the vmd command (in CONAN). Make sure that no instance of VMD is running when CONAN is started.

CONAN-build: vmd

once VMD is started, any changes to the structures are shown in the VMD window. If VMD is unavailable, the structures are saved in structures/structure.xyz. All available commands and their usage are listed here:

Note

Structures are built by using the following default parameters:

  • Carbon-carbon distance is set to 1.42 Angstroms.

  • Interlayer distance between carbon layers is set to 3.35 Angstroms. The layers are shifted with respect to each other, resulting in an ABA stacking.

  • Boron-nitride distance is 1.44 Angstroms.

  • Interlayer distance between boron nitride layers is set to 3.33 Angstroms. The positions of all nitrogen and boron atoms are switched in successive layers, resulting in an ABA stacking.

All set values can be freely adjusted by the user. All relevant values are printed to the terminal and to the conan.log file. The xyz structures are written to separate files in a structures folder.

commands