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All results from a given calculation for HCCO (ketenyl radical)

using model chemistry: QCISD/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C*V 2Π
1 2 no CS 2A"

Conformer 1 (C*V)

Jump to S1C2
Energy calculated at QCISD/3-21G
 hartrees
Energy at 0K-150.534901
Energy at 298.15K 
HF Energy-150.241203
Nuclear repulsion energy51.452339
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/3-21G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Σ 3450 3344 68.72      
2 Σ 1963 1902 22.89      
3 Σ 1220 1183 12.80      
4 Π 588 570 16.65      
4 Π 549 532 0.38      
5 Π 447 433 18.66      
5 Π 267 259 142.05      

Unscaled Zero Point Vibrational Energy (zpe) 4242.0 cm-1
Scaled (by 0.9692) Zero Point Vibrational Energy (zpe) 4111.3 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 QCISD/3-21G
B
0.34637

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD/3-21G

Point Group is C∞v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.000
C2 0.000 0.000 -1.258
O3 0.000 0.000 1.234
H4 0.000 0.000 -2.324

Atom - Atom Distances (Å)
  C1 C2 O3 H4
C11.25861.23372.3244
C21.25862.49231.0658
O31.23372.49233.5581
H42.32441.06583.5581

picture of ketenyl radical state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H4 180.000 C2 C1 O3 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (CS)

Jump to S1C1
Energy calculated at QCISD/3-21G
 hartrees
Energy at 0K-150.534901
Energy at 298.15K 
HF Energy-150.241194
Nuclear repulsion energy51.446096
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/3-21G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A' 3450 3344 68.65      
2 A' 1962 1901 22.58      
3 A' 1219 1182 12.79      
4 A' 549 532 0.37      
5 A' 269 260 141.93      
6 A" 501 486 8.35      

Unscaled Zero Point Vibrational Energy (zpe) 3974.8 cm-1
Scaled (by 0.9692) Zero Point Vibrational Energy (zpe) 3852.4 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/3-21G
B
0.34630

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD/3-21G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.000
C2 1.068 -0.665 0.000
O3 -1.048 0.652 0.000
H4 1.974 -1.227 0.000

Atom - Atom Distances (Å)
  C1 C2 O3 H4
C11.25851.23402.3244
C21.25852.49251.0659
O31.23402.49253.5584
H42.32441.06593.5584

picture of ketenyl radical state 1 conformation 2
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H4 179.886 C2 C1 O3 179.957
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability