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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: MP2/TZVP

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/TZVP
 hartrees
Energy at 0K-152.113179
Energy at 298.15K 
HF Energy-151.637128
Nuclear repulsion energy61.174168
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/TZVP
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 3455 3275 2.67 99.60 0.19 0.32
2 A1 1790 1696 3.54 37.83 0.11 0.21
3 A1 1098 1041 4.58 5.25 0.35 0.52
4 A1 890 844 53.84 8.71 0.46 0.63
5 A2 531 503 0.00 1.72 0.75 0.86
6 B1 499 473 94.15 0.40 0.75 0.86
7 B2 3386 3209 53.17 16.72 0.75 0.86
8 B2 976 926 7.05 1.58 0.75 0.86
9 B2 113i 108i 1.75 16.79 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 6255.0 cm-1
Scaled (by 0.9479) Zero Point Vibrational Energy (zpe) 5929.1 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/TZVP
ABC
1.11064 0.87120 0.48823

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/TZVP

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.899
C2 0.000 0.635 -0.466
C3 0.000 -0.635 -0.466
H4 0.000 1.650 -0.801
H5 0.000 -1.650 -0.801

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50491.50492.36862.3686
C21.50491.27081.06872.3100
C31.50491.27082.31001.0687
H42.36861.06872.31003.3005
H52.36862.31001.06873.3005

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 65.026 O1 C2 H4 133.241
O1 C3 C2 65.026 O1 C3 H5 133.241
C2 O1 C3 49.948 C2 C3 H5 161.734
C3 C2 H4 161.734
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability