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

using model chemistry: QCISD/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 QCISD/6-311G*
 hartrees
Energy at 0K-75.721709
Energy at 298.15K-75.718682
HF Energy-75.393356
Nuclear repulsion energy15.126565
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 QCISD/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 1835 1757 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 917.4 cm-1
Scaled (by 0.9574) Zero Point Vibrational Energy (zpe) 878.3 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 QCISD/6-311G*
B
1.77141

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.630
C2 0.000 0.000 -0.630

Atom - Atom Distances (Å)
  C1 C2
C11.2594
C21.2594

picture of Carbon diatomic state 1 conformation 1
More geometry information
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability

State 2 (3Πu)

Jump to S1C1
Energy calculated at QCISD/6-311G*
 hartrees
Energy at 0K-75.729791
Energy at 298.15K-75.726761
HF Energy-75.486701
Nuclear repulsion energy14.396540
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 QCISD/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 1642 1572 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 821.0 cm-1
Scaled (by 0.9574) Zero Point Vibrational Energy (zpe) 786.0 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 QCISD/6-311G*
B
1.60455

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.662
C2 0.000 0.000 -0.662

Atom - Atom Distances (Å)
  C1 C2
C11.3233
C21.3233

picture of Carbon diatomic state 2 conformation 1
More geometry information
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability