An input file for Si6(CH3)6 is:
# MIN/ONIOM(B3LYP/6-31G*:PM6)
0 1
Si 1.072140325305 0.674813020194 1.465051372146 H
Si 1.188721352253 1.229683160626 -0.824059022819 H
Si 1.509587113137 -1.078536796924 -0.229815920089 H
Si -1.174684242151 0.850690516075 -1.073040898584 H
Si -1.288038513039 0.174481898509 1.180210342195 H
Si -0.818653679090 -1.559721151184 -0.409581739300 H
C 1.700304057386 0.106828207386 3.121071775695 L H 1
C 2.425703517393 2.327128197190 -1.675580903631 L H 2
C 2.729898977208 -2.289656339913 -0.939483735774 L H 3
C -2.759542422584 1.682302545898 -1.579248345281 L H 4
C -2.985434963817 0.584018968807 1.821088393244 L H 5
C -1.969202613400 -2.922018480012 -0.938716069552 L H 6
External Atoms
H 2.588688501005 -0.491627141158 2.983143258707 L
H 1.936356529930 0.966483422949 3.730720970057 L
H 0.940610691963 -0.484199970248 3.610920408216 L
H 3.079066772767 1.724661829911 -2.289218200209 L
H 1.905728363057 3.041343609312 -2.296807257699 L
H 3.010542511047 2.852606585939 -0.935151422937 L
H 2.831448837713 -2.118222994635 -2.000944160633 L
H 3.688618120746 -2.157468019888 -0.460125985877 L
H 2.378191382490 -3.296531319323 -0.769470370638 L
H -3.314406359626 1.029646307452 -2.236945727189 L
H -3.350690803140 1.895542964114 -0.700913491119 L
H -2.533778074969 2.604596207294 -2.093840282295 L
H -3.705404475582 -0.099386423372 1.395646302768 L
H -2.995464441613 0.493557287521 2.897246417748 L
H -3.241021010195 1.595681760676 1.542495198587 L
H -1.658756712062 -3.851812748123 -0.485388418720 L
H -2.975066592717 -2.686272822946 -0.623975476951 L
H -1.941853132974 -3.018957127817 -2.014009008016 L
Options
MicroIt = (MMOnly)
Atoms shown below the External Atoms keyword are optimized before every geometrical displacement of the other atoms (microiteration). In other words, optimization is made in a geometrical subspace in which δV/δQn = 0 for coordinates of external atoms Qn. This keyword is available not only with ONIOM but also with any single-layer calculations. In double-ended (2PSHS, SCW, and DS-AFIR) calculations, the External Atoms keyword is not required in the reactant (second) structure input.
When a molecular mechanics (MM) method (UFF, AMBER, or DREIDING) is used as one layer, the atom type and the MM charge should be given for all atoms; each coordinate line should be given as follows:
[atom]-[atom type]-[MM charge] [xyz] [ONIOM-layer] [link-atom]
In double-ended (2PSHS, SCW, and DS-AFIR) calculations, designations of the atom type, the MM charge, the ONIOM layer, and the link-atom are not required in the reactant (second) structure input.
Availability
Available external software
- Gaussian 03/09/16