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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: MP2/STO-3G

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/STO-3G
 hartrees
Energy at 0K-149.804826
Energy at 298.15K 
HF Energy-149.616130
Nuclear repulsion energy59.609477
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/STO-3G
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 3642 3176 11.36 58.06 0.23 0.37
2 A1 1787 1558 0.22 7.97 0.16 0.28
3 A1 1256 1095 0.37 3.00 0.22 0.36
4 A1 956 834 0.26 6.59 0.60 0.75
5 A2 738 643 0.00 0.17 0.75 0.86
6 B1 575 502 36.07 0.78 0.75 0.86
7 B2 3566 3109 83.90 16.79 0.75 0.86
8 B2 1046 912 8.99 1.72 0.75 0.86
9 B2 597 521 2.80 10.04 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 7082.2 cm-1
Scaled (by 0.8719) Zero Point Vibrational Energy (zpe) 6174.9 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/STO-3G
ABC
1.06496 0.81946 0.46311

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/STO-3G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.927
C2 0.000 0.654 -0.469
C3 0.000 -0.654 -0.469
H4 0.000 1.660 -0.895
H5 0.000 -1.660 -0.895

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.54201.54202.46512.4651
C21.54201.30841.09262.3535
C31.54201.30842.35351.0926
H42.46511.09262.35353.3209
H52.46512.35351.09263.3209

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.895 O1 C2 H4 138.038
O1 C3 C2 64.895 O1 C3 H5 138.038
C2 O1 C3 50.209 C2 C3 H5 157.067
C3 C2 H4 157.067
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability