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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: QCISD(T)/aug-cc-pVTZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at QCISD(T)/aug-cc-pVTZ
 hartrees
Energy at 0K-152.247198
Energy at 298.15K 
HF Energy-151.645263
Nuclear repulsion energy61.124277
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)/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 A1 3395 3282        
2 A1 1755 1696        
3 A1 1060 1025        
4 A1 870 841        
5 A2 588 568        
6 B1 505 488        
7 B2 3322 3212        
8 B2 957 925        
9 B2 152 147        

Unscaled Zero Point Vibrational Energy (zpe) 6301.1 cm-1
Scaled (by 0.9668) Zero Point Vibrational Energy (zpe) 6091.9 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)/aug-cc-pVTZ
ABC
1.10284 0.87453 0.48775

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.897
C2 0.000 0.638 -0.465
C3 0.000 -0.638 -0.465
H4 0.000 1.656 -0.796
H5 0.000 -1.656 -0.796

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50391.50392.36782.3678
C21.50391.27541.07042.3171
C31.50391.27542.31711.0704
H42.36781.07042.31713.3115
H52.36782.31711.07043.3115

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.911 O1 C2 H4 133.078
O1 C3 C2 64.911 O1 C3 H5 133.078
C2 O1 C3 50.177 C2 C3 H5 162.011
C3 C2 H4 162.011
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability