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

using model chemistry: CCD/cc-pVDZ

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-pVDZ
 hartrees
Energy at 0K-75.687101
Energy at 298.15K-75.684075
HF Energy-75.386899
Nuclear repulsion energy15.089708
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-pVDZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 Σg 1882 1800 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 940.8 cm-1
Scaled (by 0.9567) Zero Point Vibrational Energy (zpe) 900.1 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-pVDZ
B
1.76279

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.631
C2 0.000 0.000 -0.631

Atom - Atom Distances (Å)
  C1 C2
C11.2625
C21.2625

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-pVDZ
 hartrees
Energy at 0K-75.707325
Energy at 298.15K-75.704297
HF Energy-75.480453
Nuclear repulsion energy14.346419
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-pVDZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 Σg 1683 1610 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 841.5 cm-1
Scaled (by 0.9567) Zero Point Vibrational Energy (zpe) 805.1 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-pVDZ
B
1.59340

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.664
C2 0.000 0.000 -0.664

Atom - Atom Distances (Å)
  C1 C2
C11.3279
C21.3279

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