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

using model chemistry: CCD/cc-pVTZ

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 CCD/cc-pVTZ
 hartrees
Energy at 0K-75.737081
Energy at 298.15K-75.734055
HF Energy-75.401441
Nuclear repulsion energy15.321870
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 CCD/cc-pVTZ
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 1901 1775 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 950.7 cm-1
Scaled (by 0.9337) Zero Point Vibrational Energy (zpe) 887.6 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 CCD/cc-pVTZ
B
1.81745

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.622
C2 0.000 0.000 -0.622

Atom - Atom Distances (Å)
  C1 C2
C11.2433
C21.2433

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 CCD/cc-pVTZ
 hartrees
Energy at 0K-75.757614
Energy at 298.15K-75.754586
HF Energy-75.496572
Nuclear repulsion energy14.568210
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 CCD/cc-pVTZ
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 1701 1588 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 850.6 cm-1
Scaled (by 0.9337) Zero Point Vibrational Energy (zpe) 794.2 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 CCD/cc-pVTZ
B
1.64305

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.654
C2 0.000 0.000 -0.654

Atom - Atom Distances (Å)
  C1 C2
C11.3077
C21.3077

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