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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: CCSD(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 CCSD(T)/aug-cc-pVTZ
 hartrees
Energy at 0K-152.246327
Energy at 298.15K 
HF Energy-151.645377
Nuclear repulsion energy61.151292
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)/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 3396 3293        
2 A1 1757 1705        
3 A1 1062 1030        
4 A1 871 845        
5 A2 590 572        
6 B1 505 490        
7 B2 3323 3223        
8 B2 958 930        
9 B2 187 182        

Unscaled Zero Point Vibrational Energy (zpe) 6324.6 cm-1
Scaled (by 0.9699) Zero Point Vibrational Energy (zpe) 6134.2 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)/aug-cc-pVTZ
ABC
1.10344 0.87560 0.48820

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.896
C2 0.000 0.638 -0.465
C3 0.000 -0.638 -0.465
H4 0.000 1.655 -0.796
H5 0.000 -1.655 -0.796

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50301.50302.36712.3671
C21.50301.27501.07032.3166
C31.50301.27502.31661.0703
H42.36711.07032.31663.3107
H52.36712.31661.07033.3107

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.904 O1 C2 H4 133.104
O1 C3 C2 64.904 O1 C3 H5 133.104
C2 O1 C3 50.193 C2 C3 H5 161.993
C3 C2 H4 161.993
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability