pair style hybrid for 3 layer graphene

sir,






I am working on graphene of 3 layers. …i got some problem with paristyle and pair coefficient …and get following error….ERROR: All pair coeffs are not set (pair.cpp:159)




code:





units metal
dimension 3
boundary s s s
atom_style full
neighbor 1.0 bin
neigh_modify every 3 delay 3
lattice fcc 2











#Reads configuration from file









read_data x80y1.txt







region 66 block INF INF INF INF INF 1.5 units box



group lower region 66


region 77 block INF INF INF INF 1.5 4.5 units box
group mid region 77



region 27 block INF INF INF INF 4.5 7 units box

group upper region 27






set group lower type 1
set group mid type 2
set group upper type 3
mass 1 12.010700
mass 2 12.010700
mass 3 12.010700


pair_style hybrid lj/cut 10 tersoff tersoff tersoff
pair_coeff * * tersoff 1 /home/cntl/lammps/potentials/C.tersoff C NULL NULL


pair_coeff * * tersoff 2 /home/cntl/lammps/potentials/C.tersoff NULL C NULL
#pair_coeff * * tersoff 3 /home/cntl/lammps/potentials/C.tersoff NULL NULL C


pair_coeff 1 2 lj/cut 0.055119926 1.412
pair_coeff 2 3 lj/cut 0.055119926 1.412


pair_coeff 1 3 none



ERROR: All pair coeffs are not set (pair.cpp:159)















for double layer my code working fine


and the code was


region 66 block INF INF INF INF INF 1.5 units box
group lower region 66
region 77 block INF INF INF INF 1.5 INF units box
group upper region 77
set group lower type 1
set group upper type 2
mass 1 12.010700
mass 2 12.010700


pair_style hybrid lj/cut 10 tersoff tersoff
pair_coeff * * tersoff 1 /home/cntl/lammps/potentials/C.tersoff C NULL


pair_coeff * * tersoff 2 /home/cntl/lammps/potentials/C.tersoff NULL C


pair_coeff 1 2 lj/cut 0.055119926 3.412





any help is greatly appreciated
regards




Ragesh
india




|

sir,
I am working on graphene of 3 layers. ..i got some problem with paristyle
and pair coefficient .........and get following error.....ERROR: All pair
coeffs are not set (pair.cpp:159)

pair_style hybrid lj/cut 10 tersoff tersoff tersoff
pair_coeff * * tersoff 1 /home/cntl/lammps/potentials/C.tersoff C NULL
NULL

pair_coeff * * tersoff 2 /home/cntl/lammps/potentials/C.tersoff NULL C
NULL
#pair_coeff * * tersoff 3 /home/cntl/lammps/potentials/C.tersoff NULL
NULL C

What happens if you uncomment this line?

pair_coeff 1 2 lj/cut 0.055119926 1.412
pair_coeff 2 3 lj/cut 0.055119926 1.412

pair_coeff 1 3 none

ERROR: All pair coeffs are not set (pair.cpp:159)

LAMMPS does not know how to calculate forces between atoms of type 3
and type 3 (or type 2 and type 3). You either need to add something
like:
pair_coeff 3 3 none
OR you could uncomment the line above beginning "#pair_coeff * * tersoff 3"

   Also, try replacing:
pair_style hybrid lj/cut 10 tersoff tersoff tersoff
   with
pair_style hybrid lj/cut 10 tersoff

Cheers
Andrew