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

using model chemistry: CCSD(T)=FULL/aug-cc-pVTZ

19 10 17 12 22

States and conformations

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

State 1 (1Σg+)

Jump to S2C1 S3C1
Energy calculated at CCSD(T)=FULL/aug-cc-pVTZ
 hartrees
Energy at 0K-75.814719
Energy at 298.15K-75.811693
HF Energy-75.401772
Nuclear repulsion energy15.303634
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 CCSD(T)=FULL/aug-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 1878 1810        

Unscaled Zero Point Vibrational Energy (zpe) 939.1 cm-1
Scaled (by 0.9637) Zero Point Vibrational Energy (zpe) 905.0 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 CCSD(T)=FULL/aug-cc-pVTZ
B
1.81424

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)=FULL/aug-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
C11.2444
C21.2444

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 S3C1
Energy calculated at CCSD(T)=FULL/aug-cc-pVTZ
 hartrees
Energy at 0K-75.814719
Energy at 298.15K-75.811693
HF Energy-75.401772
Nuclear repulsion energy15.303634
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 CCSD(T)=FULL/aug-cc-pVTZ
Rotational Constants (cm-1) from geometry optimized at CCSD(T)=FULL/aug-cc-pVTZ
B
1.81424

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)=FULL/aug-cc-pVTZ

Point Group is D∞h

Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 3 (3Σg-)

Jump to S1C1 S2C1
Energy calculated at CCSD(T)=FULL/aug-cc-pVTZ
 hartrees
Energy at 0K-75.810982
Energy at 298.15K-75.807953
HF Energy-75.496906
Nuclear repulsion energy14.514015
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 CCSD(T)=FULL/aug-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 1663 1603        

Unscaled Zero Point Vibrational Energy (zpe) 831.5 cm-1
Scaled (by 0.9637) Zero Point Vibrational Energy (zpe) 801.3 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 CCSD(T)=FULL/aug-cc-pVTZ
B
1.63181

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)=FULL/aug-cc-pVTZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.656
C2 0.000 0.000 -0.656

Atom - Atom Distances (Å)
  C1 C2
C11.3122
C21.3122

picture of Carbon diatomic state 3 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability