rho -rc

hello dear
i want to simulate water and cu .so i want to compute viscosity
i don’t know what’s rho and rc (rho_e = electronic density).can anybody give me some information or charter to find the quantity for system
thanks
regard

atom_style full
bond_style harmonic #hybrid harmonic
angle_style harmonic #hybrid harmonic
kspace_style pppm 1.0e-5
#pair_modify mix arithmetic

variable x equal 23.41
variable y equal 23.41
variable z equal 23.41

variable rho equal 0.6
variable t equal 1.0
variable rc equal 2.5

variable p equal 40 # correlation length
variable s equal 5 # sample interval
variable d equal $p*$s # dump interval

read_data water.data

group hydrogen type 1
group water type 1 2
group cu type 3
group oxygen type 2

lattice fcc 3.615 #Cu lattice constant
region Cu sphere 0 0 0 7 units box
create_atoms 3 region Cu

set group oxygen charge -1.040 #???
set group hydrogen charge .520 #???
set group cu charge 0.000

pair_style hybrid lj/cut/coul/long 0.1521 3.157 eam lj/cut 3.157 # 7.5

pair_coeff 1 1 lj/cut/coul/long 0.0460 0.4000 #H-H epsilon sigm # 108.0e-21 32.0e-11
pair_coeff 1 2 lj/cut/coul/long 0.0836 1.7753 #O-H epsilon sigma
pair_coeff 1 3 lj/cut 0.6589 0.2117 #H-Cu epsilon sigma
pair_coeff 2 2 lj/cut/coul/long 0.1521 3.157 #O-O epsilon sigma # 0 0
pair_coeff 2 3 lj/cut 1.198 1.587 #O-Cu epsilon sigma
pair_coeff 3 3 eam cu.eam #Cu-Cu

for cu-cu bond sigma=.227 epsilon(Lj)=.583 ev # sigma=2.34 epsilon=9.4512 kcal/mol

bond_coeff 1 450 0.9572 #O-H
angle_coeff 1 55 104.52 #H-O-H

++++++++++++++++setting+++++++++++++++++++++

neighbor 2.0 bin
neigh_modify delay 0 every 1 check yes
#Unlike “fix rigid”, there is no need to use "neigh_modify

exclude" if you use “fix shake”

---------- Relaxation -----------------------------------------

minimization : avoid atoms overlapping

#min_style fire
min_modify dmax 0.01
minimize 1.0e-8 0 10000 30000
reset_timestep 0

hello dear
i want to simulate water and cu .so i want to compute viscosity
i don’t know what’s rho and rc (rho_e = electronic density).can anybody give me some information or charter to find the quantity for system
thanks
regard

atom_style full
bond_style harmonic #hybrid harmonic
angle_style harmonic #hybrid harmonic
kspace_style pppm 1.0e-5
#pair_modify mix arithmetic

variable x equal 23.41
variable y equal 23.41
variable z equal 23.41

variable rho equal 0.6
variable t equal 1.0
variable rc equal 2.5

variable p equal 40 # correlation length
variable s equal 5 # sample interval
variable d equal $p*$s # dump interval

read_data water.data

group hydrogen type 1
group water type 1 2
group cu type 3
group oxygen type 2

lattice fcc 3.615 #Cu lattice constant
region Cu sphere 0 0 0 7 units box
create_atoms 3 region Cu

set group oxygen charge -1.040 #???
set group hydrogen charge .520 #???
set group cu charge 0.000

pair_style hybrid lj/cut/coul/long 0.1521 3.157 eam lj/cut 3.157 # 7.5

pair_coeff 1 1 lj/cut/coul/long 0.0460 0.4000 #H-H epsilon sigm # 108.0e-21 32.0e-11
pair_coeff 1 2 lj/cut/coul/long 0.0836 1.7753 #O-H epsilon sigma
pair_coeff 1 3 lj/cut 0.6589 0.2117 #H-Cu epsilon sigma
pair_coeff 2 2 lj/cut/coul/long 0.1521 3.157 #O-O epsilon sigma # 0 0
pair_coeff 2 3 lj/cut 1.198 1.587 #O-Cu epsilon sigma
pair_coeff 3 3 eam cu.eam #Cu-Cu

for cu-cu bond sigma=.227 epsilon(Lj)=.583 ev # sigma=2.34 epsilon=9.4512 kcal/mol

bond_coeff 1 450 0.9572 #O-H
angle_coeff 1 55 104.52 #H-O-H

++++++++++++++++setting+++++++++++++++++++++

neighbor 2.0 bin
neigh_modify delay 0 every 1 check yes
#Unlike “fix rigid”, there is no need to use "neigh_modify

exclude" if you use “fix shake”

---------- Relaxation -----------------------------------------

minimization : avoid atoms overlapping

#min_style fire
min_modify dmax 0.01
minimize 1.0e-8 0 10000 30000
reset_timestep 0