return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C2H2O (Oxirene)

using model chemistry: CCSD(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 CCSD(T)/6-311+G(3df,2p)
 hartrees
Energy at 0K-152.233500
Energy at 298.15K 
HF Energy-151.641855
Nuclear repulsion energy61.316857
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 CCSD(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 3397 3353        
2 A1 1763 1740        
3 A1 1074 1060        
4 A1 879 868        
5 A2 591 583        
6 B1 501 494        
7 B2 3330 3286        
8 B2 962 949        
9 B2 199 196        

Unscaled Zero Point Vibrational Energy (zpe) 6347.3 cm-1
Scaled (by 0.9869) Zero Point Vibrational Energy (zpe) 6264.2 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 CCSD(T)/6-311+G(3df,2p)
ABC
1.10424 0.88475 0.49119

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(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 -0.790
H5 0.000 -1.657 -0.790

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.49661.49662.36062.3606
C21.49661.27361.07122.3169
C31.49661.27362.31691.0712
H42.36061.07122.31693.3137
H52.36062.31691.07123.3137

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.817 O1 C2 H4 132.963
O1 C3 C2 64.817 O1 C3 H5 132.963
C2 O1 C3 50.366 C2 C3 H5 162.220
C3 C2 H4 162.220
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability