45 lines
1.6 KiB
Plaintext
45 lines
1.6 KiB
Plaintext
# Charge regulation lammps for simple weak electrolyte
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units real
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atom_style charge
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neighbor 10.0 bin
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read_data data.chreg-acid-real
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#real units
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variable sigma equal 7.2 # particle diameter 0.72 nm
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variable temperature equal 298 # temperature 298 K
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variable kb index 0.0019872067 # kB in Kcal/mol/K
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variable epsilon equal ${kb}*${temperature}
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variable tunit equal 2000 # time unit is 2000 fs
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variable timestep equal 0.005*${tunit}
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variable cut_long equal 12.5*${sigma}
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variable nevery equal 100
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variable nmc equal 100
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variable pH equal 7.0
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variable pKa equal 6.0
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variable pIm equal 3.0
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variable pIp equal 3.0
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variable cut_lj equal 2^(1.0/6.0)*${sigma}
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velocity all create ${temperature} 8008 loop geom
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pair_style lj/cut/coul/long ${cut_lj} ${cut_long}
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pair_coeff * * ${epsilon} ${sigma}
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kspace_style pppm 1.0e-3
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dielectric 78
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pair_modify shift yes
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######### VERLET INTEGRATION WITH LANGEVIN THERMOSTAT ###########
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fix fnve all nve
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compute dtemp all temp
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compute_modify dtemp dynamic yes
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fix fT all langevin $(v_temperature) $(v_temperature) $(v_tunit) 123
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fix_modify fT temp dtemp
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fix chareg all charge/regulation 2 3 acid_type 1 pH ${pH} pKa ${pKa} pIp ${pIp} pIm ${pIm} lunit_nm 0.1 nevery ${nevery} nmc ${nmc} seed 2345 tempfixid fT
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thermo 100
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thermo_style custom step pe c_dtemp f_chareg[1] f_chareg[2] f_chareg[3] f_chareg[4] f_chareg[5] f_chareg[6] f_chareg[7] f_chareg[8]
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timestep ${timestep}
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run 2000
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