QM region input


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Hello,

I tried to compute a QMMM calculation from a pdb file. First of all, I want to create the topology and restart file using the prepare module. I read the documentation about the preparation of this file but I do not understand what im doing wrong...

Here is my PDB file :

ATOM    1  1C0   RE1     1       8.779   4.095   0.000  1.00  0.00           C
ATOM    3  1C2   RE1     1       2.925   0.000   0.000  1.00  0.00           C
ATOM    4  1C3   RE1     1       2.925   8.189   0.000  1.00  0.00           C
ATOM    5  1C4   RE1     1       2.925   0.000   8.184  1.00  0.00           C
ATOM    6  1C5   RE1     1       2.925   8.189   8.184  1.00  0.00           C
...
ATOM    2  1C1   RE2     2       8.779   4.095   8.184  1.00  0.00           C
ATOM   19  1H0   RE2     2       9.378   4.746   7.641  1.00  0.00           H
ATOM   39  3H0   RE2     2       8.179   3.552   7.533  1.00  0.00           H
ATOM  105  8H4   RE2     2       9.378   3.443   8.727  1.00  0.00           H
ATOM  106  8H5   RE2     2       8.179   4.638   8.836  1.00  0.00           H




My input file is :


 title "QMMM cell"

 echo

 start qmmm_cell

 prepare
 source cell1.pdb
 new_top new_seq
 new_rst

#define quantum region residue:name
        #modify atom 2:1C1 quantum
        #modify atom 2:1H0 quantum
        #modify atom 2:3H0 quantum
        #modify atom 2:8H4 quantum
        #modify atom 2:8H5 quantum
         modify segment 2 quantum

 update lists
 ignore
 write cell.rst
 write qmmm.pdb
 end


Unfortunetly, the qmmm.pdb file does not want to be created and I have this output file:

 
 ...
 Coordinates missing for atom     1:RE1       H7
 Coordinates missing for atom     1:RE1       H8
 Coordinates missing for atom     1:RE1       H9
 Coordinates missing for atom     1:RE1       H0
 Coordinates missing for atom     1:RE1       H1
 Coordinates missing for atom     1:RE1       H6
 Coordinates missing for atom     1:RE1       H7
 Coordinates missing for atom     1:RE1       H8
 Coordinates missing for atom     1:RE1       H5
 Coordinates missing for atom     1:RE1       H6
 Coordinates missing for atom     1:RE1       H7
 Added counterion with energy                 0.000 kJ/mol
 Grid specifications for non-bonded atoms done


 **********
 *   0: pre_misfit: missing non hydrogen coordinates 9999


You can remark that I fixed 2 different residual name. The first one is the MM region and the second is the QM region that I want to define in the prepare module.

When I define the QM region atom per atom with the commented command, I obtain another output :


 modify atom     2:1C1    set 0 quantum

 **********
 *   0: Atom not found for quantum    0



What I am doing wrong? How can I define QM and MM region in the input file?

Thank you in advance!
Guillaume