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All results from a given calculation for C4 (Carbon tetramer)

using model chemistry: QCISD/6-31G(2df,p)

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D*H 3Σg
2 1 yes D*H 1Σ

State 1 (3Σg)

Jump to S2C1
Energy calculated at QCISD/6-31G(2df,p)
 hartrees
Energy at 0K-151.711228
Energy at 298.15K 
HF Energy-151.199429
Nuclear repulsion energy63.297621
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/6-31G(2df,p)
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 2178 2063 0.00      
2 Σg 945 895 0.00      
3 Σu 1608 1524 254.20      
4 Πg 360 341 0.00      
4 Πg 360 341 0.00      
5 Πu 179 169 22.97      
5 Πu 179 169 22.97      

Unscaled Zero Point Vibrational Energy (zpe) 2903.9 cm-1
Scaled (by 0.9474) Zero Point Vibrational Energy (zpe) 2751.2 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 QCISD/6-31G(2df,p)
B
0.16534

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD/6-31G(2df,p)

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.644
C2 0.000 0.000 -0.644
C3 0.000 0.000 1.958
C4 0.000 0.000 -1.958

Atom - Atom Distances (Å)
  C1 C2 C3 C4
C11.28881.31342.6022
C21.28882.60221.3134
C31.31342.60223.9156
C42.60221.31343.9156

picture of Carbon tetramer state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 180.000 C2 C1 C3 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 2 (1Σ)

Jump to S1C1
Energy calculated at QCISD/6-31G(2df,p)
 hartrees
Energy at 0K-151.692564
Energy at 298.15K 
HF Energy-151.148488
Nuclear repulsion energy63.101518
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/6-31G(2df,p)
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 2129 2017 0.00      
2 Σg 933 883 0.00      
3 Σu 1595 1511 370.46      
4 Πg 453 429 0.00      
4 Πg 250 236 0.00      
5 Πu 208 198 7.63      
5 Πu 151 143 30.79      

Unscaled Zero Point Vibrational Energy (zpe) 2859.0 cm-1
Scaled (by 0.9474) Zero Point Vibrational Energy (zpe) 2708.6 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 QCISD/6-31G(2df,p)
B
0.16429

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD/6-31G(2df,p)

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.648
C2 0.000 0.000 -0.648
C3 0.000 0.000 1.964
C4 0.000 0.000 -1.964

Atom - Atom Distances (Å)
  C1 C2 C3 C4
C11.29581.31572.6115
C21.29582.61151.3157
C31.31572.61153.9271
C42.61151.31573.9271

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