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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: QCISD(T)/6-311+G(3df,2p)

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)/6-311+G(3df,2p)
 hartrees
Energy at 0K-152.234344
Energy at 298.15K 
HF Energy-151.641703
Nuclear repulsion energy61.278690
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)/6-311+G(3df,2p)
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 3396 3238        
2 A1 1759 1677        
3 A1 1071 1022        
4 A1 877 836        
5 A2 588 561        
6 B1 500 476        
7 B2 3328 3174        
8 B2 960 916        
9 B2 162 155        

Unscaled Zero Point Vibrational Energy (zpe) 6320.0 cm-1
Scaled (by 0.9537) Zero Point Vibrational Energy (zpe) 6027.4 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(T)/6-311+G(3df,2p)
ABC
1.10349 0.88311 0.49054

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD(T)/6-311+G(3df,2p)

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.892
C2 0.000 0.637 -0.463
C3 0.000 -0.637 -0.463
H4 0.000 1.657 -0.791
H5 0.000 -1.657 -0.791

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.49781.49782.36202.3620
C21.49781.27421.07132.3175
C31.49781.27422.31751.0713
H42.36201.07132.31753.3143
H52.36202.31751.07133.3143

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.827 O1 C2 H4 132.974
O1 C3 C2 64.827 O1 C3 H5 132.974
C2 O1 C3 50.345 C2 C3 H5 162.198
C3 C2 H4 162.198
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability