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

using model chemistry: MP2/TZVP

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 MP2/TZVP
 hartrees
Energy at 0K-75.723663
Energy at 298.15K-75.720637
HF Energy-75.398684
Nuclear repulsion energy15.135976
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 MP2/TZVP
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 1893 1794 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 946.5 cm-1
Scaled (by 0.9479) Zero Point Vibrational Energy (zpe) 897.2 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 MP2/TZVP
B
1.77361

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/TZVP

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.629
C2 0.000 0.000 -0.629

Atom - Atom Distances (Å)
  C1 C2
C11.2586
C21.2586

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 MP2/TZVP
 hartrees
Energy at 0K-75.713978
Energy at 298.15K-75.710949
HF Energy-75.491883
Nuclear repulsion energy14.487522
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 MP2/TZVP
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 1668 1581 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 834.1 cm-1
Scaled (by 0.9479) Zero Point Vibrational Energy (zpe) 790.7 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 MP2/TZVP
B
1.62490

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/TZVP

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
C11.3084
C21.3084

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