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geometry_optimization_and_molecular_orbitals_mos_calculation

General setup

  • Firstly, generate a Z-matrix using OpenBabel, Molden, …
  • Then, paste the next lines at the beginning of the document, according to your needs:
  • NOTE: This is not a Gaussian tutorial; it is only a (very brief) summary of some input possibilities.
  • GEOMETRY OPTIMIZATION

%chk=your_file_name
%nproc=1 Number of processor(s) that are going to be used.
#p B3LYP/6-311+G(d,p) opt=Z-matrix scf=tight/direct scrf=(iefpcm,solvent=m-xylene) Quantum method and basis set. Use scrf if you want to take into account the solvent effect.
(space)
molecule geometry optimization Describe here what you are working on.
(space)
-1 1 Total charge of the quantum system and spin multiplicity (unpaired electrons = 1; 1 unpaired electron = 2 (singlet); 2 unpaired electrons = 3 (doublet), …

  • TRANSITION STATE SEEKING

%chk=your_file_name
%nproc=1 Number of processor(s) that are going to be used.
#p B3LYP/6-311+G(d,p) opt=(TS,CalcFc,NoEigenTest) Freq Now, keyword opt has TS as the argument. If the TS geometry is unknown, you can use QST2/QST3 instead of TS. The former implies that the reactant and final product geometries (in this order) need to be specified. The latter requires, in addition, a guess of the TS geometry at the end of the input.
(space)
TS geometry seeking !Describe here what you are working on.
(space)
-1 1 Total charge of the quantum system and spin multiplicity (unpaired electrons = 1; 1 unpaired electron = 2 (singlet); 2 unpaired electrons = 3 (doublet), …

  • MOLECULAR ORBITALS (MOs) CALCULATION

%chk=your_file_name
%nproc=1 Number of processor(s) that are going to be used.
#p B3LYP/6-311+G(d,p) pop=full iop(6/7=3) GFinput Quantum method and basis set. We specify GFinput because we usually visualize the results in Molden or gmolden.
(space)
1attack MO visualization Describe here what you are working on.
(space)
-1 1 Total charge of the quantum system and spin multiplicity (unpaired electrons = 1; 1 unpaired electron = 2 (singlet); 2 unpaired electrons = 3 (doublet), …

geometry_optimization_and_molecular_orbitals_mos_calculation.txt · Last modified: 2016/12/16 07:01 by root