Incorrect args for pair coefficients

Hello
I made a cube of Al fcc then delete an inner cube of atoms and placed a Si diamond.
I used hybrid form of atom_style. It comes up with "Incorrect args for pair coefficient"
I write down here the related commands I used in program.

units metal
boundary s s s
atom_style atomic
#Al lattice definition
lattice fcc 4.05
region r1 block 0 5 0 5 0 5 units lattice
create_box 2 r1
create_atoms 1 region r1
#Deleting inner atoms
region delete1 block 1 4.5 1 4.5 1 4.5 units lattice
delete_atoms region delete1
#Si lattice definition
lattice diamond 5.43
region r2 block 1 4 1 4 1 4 units lattice
create_atoms 2 region r2

mass 2 28.0855

pair_style hybrid eam/alloy sw lj/cut 4
pair_coeff 1 1 eam/alloy Al99.eam.alloy Al
pair_coeff 2 2 Si.tersoff Si
pair_coeff 1 2 lj/cut 0.4121 2.3216

I didn't enter Al mass cause it's potential is eam/alloy.
Thank You.

This line:
pair_coeff 2 2 Si.tersoff Si
needs to be something like:
pair_coeff 2 2 sw Si.tersoff NULL Si

The SW doc page discusses this in detail.

Steve