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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: MP2=FULL/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at MP2=FULL/6-31G*
 hartrees
Energy at 0K-152.030678
Energy at 298.15K 
HF Energy-151.580388
Nuclear repulsion energy60.959561
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 MP2=FULL/6-31G*
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 3459 3260 2.13 97.87 0.20 0.33
2 A1 1803 1699 1.39 24.67 0.20 0.33
3 A1 1109 1045 2.83 4.71 0.28 0.43
4 A1 891 839 42.49 7.71 0.45 0.62
5 A2 479 451 0.00 0.24 0.75 0.86
6 B1 485 457 84.22 0.72 0.75 0.86
7 B2 3391 3195 39.79 16.70 0.75 0.86
8 B2 952 897 7.22 3.31 0.75 0.86
9 B2 10i 10i 0.56 12.89 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 6279.1 cm-1
Scaled (by 0.9422) Zero Point Vibrational Energy (zpe) 5916.1 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 MP2=FULL/6-31G*
ABC
1.10184 0.86595 0.48488

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/6-31G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.901
C2 0.000 0.638 -0.467
C3 0.000 -0.638 -0.467
H4 0.000 1.658 -0.801
H5 0.000 -1.658 -0.801

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50981.50982.37632.3763
C21.50981.27531.07352.3197
C31.50981.27532.31971.0735
H42.37631.07352.31973.3158
H52.37632.31971.07353.3158

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 65.017 O1 C2 H4 133.099
O1 C3 C2 65.017 O1 C3 H5 133.099
C2 O1 C3 49.965 C2 C3 H5 161.883
C3 C2 H4 161.883
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability