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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: PM3

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
Energy calculated at PM3
 hartrees
Energy at 0K 
Energy at 298.15K0.083535
HF Energy0.083535
Nuclear repulsion energy47.236319
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 PM3
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 3293 3208 14.82 16.42 0.28 0.44
2 A1 1948 1898 1.26 130.78 0.22 0.36
3 A1 1194 1163 10.27 29.18 0.75 0.86
4 A1 937 913 23.33 6.97 0.75 0.86
5 A2 843 822 0.00 47.86 0.75 0.86
6 B1 749 729 103.03 0.18 0.75 0.86
7 B2 3243 3158 205.73 4.89 0.75 0.86
8 B2 1021 994 0.18 0.28 0.75 0.86
9 B2 668 651 11.09 66.33 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 6947.9 cm-1
Scaled (by 0.974) Zero Point Vibrational Energy (zpe) 6767.3 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 PM3
ABC
1.07057 0.95458 0.50463

See section I.F.4 to change rotational constant units
Geometric Data calculated at PM3

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.858
C2 0.000 0.649 -0.444
C3 0.000 -0.649 -0.444
H4 0.000 1.674 -0.767
H5 0.000 -1.674 -0.767

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.45541.45542.33352.3335
C21.45541.29741.07482.3448
C31.45541.29742.34481.0748
H42.33351.07482.34483.3476
H52.33352.34481.07483.3476

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 63.531 O1 C2 H4 133.957
O1 C3 C2 63.531 O1 C3 H5 133.957
C2 O1 C3 52.937 C2 C3 H5 162.511
C3 C2 H4 162.511
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability