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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: MP2/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at MP2/3-21G*
 hartrees
Energy at 0K-151.035861
Energy at 298.15K 
HF Energy-150.723832
Nuclear repulsion energy58.625285
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 MP2/3-21G*
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 3424 3257 4.02 88.60 0.18 0.30
2 A1 1707 1624 3.04 20.38 0.24 0.39
3 A1 1060 1008 1.44 2.68 0.38 0.55
4 A1 841 800 14.35 7.91 0.42 0.60
5 A2 535 509 0.00 0.78 0.75 0.86
6 B1 532 506 111.59 1.07 0.75 0.86
7 B2 3356 3192 27.83 20.59 0.75 0.86
8 B2 961 914 10.86 1.59 0.75 0.86
9 B2 193 184 2.58 13.18 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 6304.1 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 5997.1 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 MP2/3-21G*
ABC
1.09523 0.74364 0.44291

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.973
C2 0.000 0.644 -0.502
C3 0.000 -0.644 -0.502
H4 0.000 1.644 -0.882
H5 0.000 -1.644 -0.882

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.60871.60872.47842.4784
C21.60871.28751.07002.3189
C31.60871.28752.31891.0700
H42.47841.07002.31893.2875
H52.47842.31891.07003.2875

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 66.412 O1 C2 H4 134.424
O1 C3 C2 66.412 O1 C3 H5 134.424
C2 O1 C3 47.176 C2 C3 H5 159.164
C3 C2 H4 159.164
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability