QMMM ESP Charge Analysis
- Example QM/MM ESP Calculation:
The example below illustrates dipole property QM/MM DFT/B3LYP calculation for quantum water molecule embedded into 20 angstrom box of classical SPCE/E water molecules.
The preparation stage that involves definition of the QM region and solvation is performed as part of the calculation. Note that water fragment file wtr.frg is required in this calculation. Prepare run will generate restart file (wtr_ref.rst) and topology file (wtr.top)
In the QM/MM interface block the use of bq_zone value of 3.0 Angstrom is specified.
start wtr permanent_dir ./perm scratch_dir ./data prepare source wtr0.pdb new_top new_seq new_rst modify segment 1 quantum center orient solvate box 3.0 update lists ignore write wtr_ref.rst write wtr_ref.pdb end task prepare md system wtr_ref end basis * library "6-31G" end dft xc b3lyp end qmmm bq_zone 3.0 end property dipole end task qmmm dft property