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All results from a given calculation for CH3CO (Acetyl radical)

using model chemistry: QCISD(T)/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 2A'
Energy calculated at QCISD(T)/3-21G
 hartrees
Energy at 0K-151.760963
Energy at 298.15K-151.763169
HF Energy-151.434579
Nuclear repulsion energy61.271568
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(T)/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' 761 726        
2 A' 435 414        
3 A" 3106 2962        
4 A" 1539 1468        
5 A" 1000 953        
6 A" 103 98        
7 A' 3100 2957        
8 A' 3017 2878        
9 A' 1676 1598        
10 A' 1534 1463        
11 A' 1417 1352        
12 A' 1059 1010        

Unscaled Zero Point Vibrational Energy (zpe) 9373.7 cm-1
Scaled (by 0.9537) Zero Point Vibrational Energy (zpe) 8939.7 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 QCISD(T)/3-21G
ABC
2.75972 0.31158 0.29570

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 -1.005 -0.679 0.000
C2 0.000 0.501 0.000
O3 1.224 0.487 0.000
H4 -0.480 -1.645 0.000
H5 -1.641 -0.592 0.891
H6 -1.641 -0.592 -0.891

Atom - Atom Distances (Å)
  C1 C2 O3 H4 H5 H6
C11.55012.51531.10011.09861.0986
C21.55011.22412.19972.16422.1642
O32.51531.22412.72913.18873.1887
H41.10012.19972.72911.80391.8039
H51.09862.16423.18871.80391.7826
H61.09862.16423.18871.80391.7826

picture of Acetyl radical state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 O3 129.716 C2 C1 H4 111.065
C2 C1 H5 108.376 C2 C1 H6 108.376
H4 C1 H5 110.255 H4 C1 H6 110.255
H5 C1 H6 108.439
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability