New user here.
I´m trying to study the adsorption of aromatic compounds on acid zeolites. I´ve built an HZSM-5 supercell cif file and the following input file but for some reason, I´m getting more than 1 benzene molecule (as selected). Since I want to study the adsorption on acid site (H-site) how can I force a single benzene molecule per acid site
----INPUT---
SimulationType MonteCarlo
NumberOfCycles 25000
NumberOfInitializationCycles 10000
PrintEvery 1000
RestartFile no
Forcefield GarciaPerez2006
Framework 0
FrameworkName MFI_1Al
RemoveAtomNumberCodeFromLabel yes
UnitCells 1 1 1
ExternalTemperature 300
ExternalPressure 10000.0
Movies yes
WriteMoviesEvery 100
Component 0 MoleculeName benzene
MoleculeDefinition TraPPE
TranslationProbability 1.0
ReinsertionProbability 1.0
SwapProbability 1.0
ExtraFrameworkMolecule no
CreateNumberOfMolecules 2
-----CIF----
_cell_length_a 20.022
_cell_length_b 19.899
_cell_length_c 26.766
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 10664.1
_symmetry_cell_setting orthorhombic
_symmetry_space_group_name_Hall 'P 1'
_symmetry_space_group_name_H-M 'P 1'
_symmetry_Int_Tables_number 1
_symmetry_equiv_pos_as_xyz 'x,y,z'
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_charge
_atom_site_polarization
_atom_site_anisotropic_displacement
_atom_site_anisotropic_type
_atom_site_print_to_pdb
Si Si 0.42238 0.05650 0.33201 Si4+ 0 0 absolute yes
Si Si 0.30716 0.02772 0.40535 Si4+ 0 0 absolute yes
Si Si 0.27911 0.06127 0.01560 Si4+ 0 0 absolute yes
Si Si 0.12215 0.06298 0.01335 Si4+ 0 0 absolute yes
Si Si 0.07128 0.02722 0.40725 Si4+ 0 0 absolute yes
Si Si 0.18641 0.05896 0.33591 Si4+ 0 0 absolute yes
Si Si 0.42265 0.82750 0.33641 Si4+ 0 0 absolute yes
Si Si 0.30778 0.86984 0.40726 Si4+ 0 0 absolute yes
Si Si 0.27554 0.82721 0.01555 Si4+ 0 0 absolute yes
Si Si 0.12058 0.82690 0.01490 Si4+ 0 0 absolute yes
Si Si 0.07044 0.86963 0.40900 Si4+ 0 0 absolute yes
Si Si 0.18706 0.82673 0.34034 Si4+ 0 0 absolute yes
O O 0.37260 0.05340 0.37790 O2- 0 0 absolute yes
O O 0.30840 0.05870 0.46055 O2- 0 0 absolute yes
O O 0.20070 0.05920 0.01445 O2- 0 0 absolute yes
O O 0.09690 0.06110 0.45720 O2- 0 0 absolute yes
O O 0.11490 0.05410 0.36185 O2- 0 0 absolute yes
O O 0.24350 0.05530 0.37700 O2- 0 0 absolute yes
O O 0.37420 0.84390 0.38140 O2- 0 0 absolute yes
O O 0.30850 0.84480 0.46360 O2- 0 0 absolute yes
O O 0.19800 0.84460 0.01440 O2- 0 0 absolute yes
O O 0.09100 0.83860 0.46115 O2- 0 0 absolute yes
O O 0.11690 0.84220 0.36530 O2- 0 0 absolute yes
O O 0.24480 0.84060 0.37890 O2- 0 0 absolute yes
O O 0.30470 0.94900 0.40670 O2- 0 0 absolute yes
O O 0.07680 0.94810 0.41155 O2- 0 0 absolute yes
.
.
.
Si Si 0.42956 0.36963 0.65900 Si4+ 0 0 absolute yes
Al Al 0.31294 0.32673 0.59034 Al3+ 0 0 absolute yes
.
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O O 0.99600 0.65280 0.89610 O2- 0 0 absolute yes
H H 0.31449 0.25063 0.53431 H1+ 0 0 absolute yes
PS. Iḿ not able to write the full cif file do to a maximum length of the post
Thanks a lot
Carlos
You're swapping molecules in and out, and hence use the grand-canonical ensemble. In this ensemble, you fix the chemical potential (via the pressure/fugacity) and the amount of molecules fluctuates. So you're not able to control how many of where the molecules are. But that is the nature of adsorption.
Btw. you're missing a rotation move (although you could say this is also achieved via insertion of molecules, this is much less efficient).