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

using model chemistry: CISD/6-311G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
2 1 yes D*H 1Σg

State 1 (3Σg)

Jump to S2C1
Vibrational Frequencies calculated at CISD/6-311G*
Rotational Constants (cm-1) from geometry optimized at CISD/6-311G*
See section I.F.4 to change rotational constant units
Geometric Data calculated at CISD/6-311G*
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 2 (1Σg)

Jump to S1C1
Energy calculated at CISD/6-311G*
 hartrees
Energy at 0K-577.856075
Energy at 298.15K-577.854814
Nuclear repulsion energy50.442310
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/6-311G*
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 619 573 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 309.6 cm-1
Scaled (by 0.9253) Zero Point Vibrational Energy (zpe) 286.5 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/6-311G*
B
0.28504

See section I.F.4 to change rotational constant units
Geometric Data calculated at CISD/6-311G*

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.028
Si2 0.000 0.000 -1.028

Atom - Atom Distances (Å)
  Si1 Si2
Si12.0562
Si22.0562

picture of Silicon diatomic state 2 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability