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All results from a given calculation for C2 (Carbon diatomic)

using model chemistry: MP4/6-311G**

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D*H 1Σg+
2 1 yes D*H 3Πu

State 1 (1Σg+)

Jump to S2C1
Energy calculated at MP4/6-311G**
 hartrees
Energy at 0K-75.759505
Energy at 298.15K-75.756477
HF Energy-75.391413
Nuclear repulsion energy14.824240
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 MP4/6-311G**
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 1731 1679        

Unscaled Zero Point Vibrational Energy (zpe) 865.7 cm-1
Scaled (by 0.9697) Zero Point Vibrational Energy (zpe) 839.4 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 MP4/6-311G**
B
1.70234

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/6-311G**

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.642
C2 0.000 0.000 -0.642

Atom - Atom Distances (Å)
  C1 C2
C11.2847
C21.2847

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

State 2 (3Πu)

Jump to S1C1
Energy calculated at MP4/6-311G**
 hartrees
Energy at 0K-75.742982
Energy at 298.15K-75.739952
HF Energy-75.485775
Nuclear repulsion energy14.283604
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 MP4/6-311G**
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 1586 1538        

Unscaled Zero Point Vibrational Energy (zpe) 792.8 cm-1
Scaled (by 0.9697) Zero Point Vibrational Energy (zpe) 768.7 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 MP4/6-311G**
B
1.58040

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/6-311G**

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.667
C2 0.000 0.000 -0.667

Atom - Atom Distances (Å)
  C1 C2
C11.3333
C21.3333

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