Error in number of solute fractions?


Clicked A Few Times
Hello:

I am trying to set-up an excited state qm/mm simulation but I keep on getting the referenced error message - and I'm not sure how I should fix it. I read through the manual and found that the error has to do with centering updates but I'm not sure. I also see that I have a warning about not specifying a reference energy. Is this required? Anyway, could someone please tell me what I am missing/doing wrong?

Thank you,

Kristina

My input file

title "Prepare QM/MM calculation for protein"

memory total 1 Gb

scratch_dir ./

charge 0

prepare
  1. --name of the pdb file
  source short_r.pdb                    
  1. --generate new topology and sequence file
  new_top new_seq
  1. --use charmm forcefield
  ffield amber
  1. --generate new restart file
  new_rst                            
  1. --define quantum region (note the use of underscore)
modify segment 313 quantum
modify segment 314 quantum
modify segment 315 quantum
modify segment 316 quantum
modify segment 317 quantum
modify segment 318 quantum
modify segment 319 quantum
modify segment 320 quantum
modify segment 321 quantum
modify segment 322 quantum
  update lists 
ignore

  1. --save restart file
  write tddft_ref.rst
  1. --generate pdb file
  write tddft_ref.pdb
end
task prepare

 md
system tddft_ref
end


qmmm
region qm mm solvent
maxiter 500 1000 3000
bq_zone 3.0
density static
xyz qm mm
end

 basis "ao basis"
* library "6-31G*"
end

 dft
xc b3lyp
maxiter 500
direct
end

 tddft
cis
nroots 16
singlet
notriplet
civecs
end
task qmmm tddft energy

And output error:
tddft_input: filename not found; default name will be used
****************************************************
* NWChem QM/MM Interface Module *
* *
* Developed Marat Valiev 2004 *
****************************************************
QM/MM Interface Parameters
--------------------------
operation task:operation energy
reference energy qmmm:uqmatm 0.000000 <--- Warning zero value is not advisable !!!
bqzone radius qmmm:bqzone 3.000000
excluded bq's qmmm:bq_exclude none
link atom type qmmm:linkatm hydrogens
optimization method qmmm:optimization bfgs
qmmm:region 1 qm
qmmm:region 2 mm
qmmm:region 3 solvent
ecp on link atoms qmmm:link_ecp auto
interface api qmmm:interface qm
------------------------------------------------------



**********
* 0: Error in number of solute fractions 0
**********
0::Received an Error in Communication

Clicked A Few Times
Re: Error in number of solute fractions?
If anyone could just give me an example of how I should specify the solute fraction in the input file - that would also be tremendously helpful.

K


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