geometry_optimization_and_molecular_orbitals_mos_calculation

- 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