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All results from a given calculation for Si2 (Silicon diatomic)

using model chemistry: CISD/cc-pVDZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D*H 3Σg
Energy calculated at CISD/cc-pVDZ
 hartrees
Energy at 0K-577.908438
Energy at 298.15K-577.907116
Nuclear repulsion energy45.631545
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at CISD/cc-pVDZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Σg 522 481        

Unscaled Zero Point Vibrational Energy (zpe) 260.9 cm-1
Scaled (by 0.9218) Zero Point Vibrational Energy (zpe) 240.5 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at CISD/cc-pVDZ
B
0.23326

See section I.F.4 to change rotational constant units
Geometric Data calculated at CISD/cc-pVDZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.136
Si2 0.000 0.000 -1.136

Atom - Atom Distances (Å)
  Si1 Si2
Si12.2730
Si22.2730

picture of Silicon diatomic state 1 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability