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All results from a given calculation for C2H4O (Ethylene oxide)

using model chemistry: CISD/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 CISD/3-21G*
 hartrees
Energy at 0K-152.297386
Energy at 298.15K 
HF Energy-151.999125
Nuclear repulsion energy73.116172
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 CISD/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 3203 2993 1.83      
2 A1 1614 1508 0.01      
3 A1 1249 1167 7.56      
4 A1 1172 1095 3.57      
5 A1 838 783 25.08      
6 A2 3275 3061 0.00      
7 A2 1232 1152 0.00      
8 A2 1031 964 0.00      
9 B1 3294 3078 35.82      
10 B1 1148 1073 1.90      
11 B1 868 811 0.02      
12 B2 3188 2979 18.61      
13 B2 1595 1490 0.08      
14 B2 1174 1097 12.63      
15 B2 811 758 2.08      

Unscaled Zero Point Vibrational Energy (zpe) 12845.9 cm-1
Scaled (by 0.9344) Zero Point Vibrational Energy (zpe) 12003.2 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 CISD/3-21G*
ABC
0.77617 0.72434 0.44133

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.906
C2 0.000 0.746 -0.396
C3 0.000 -0.746 -0.396
H4 0.918 1.273 -0.623
H5 -0.918 1.273 -0.623
H6 -0.918 -1.273 -0.623
H7 0.918 -1.273 -0.623

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5 H6 H7
O11.50061.50062.19092.19092.19092.1909
C21.50061.49151.08251.08252.22892.2289
C31.50061.49152.22892.22891.08251.0825
H42.19091.08252.22891.83603.13842.5453
H52.19091.08252.22891.83602.54533.1384
H62.19092.22891.08253.13842.54531.8360
H72.19092.22891.08252.54533.13841.8360

picture of Ethylene oxide state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 60.201 O1 C2 H4 115.068
O1 C2 H5 115.068 O1 C3 C2 60.201
O1 C3 H6 115.068 O1 C3 H7 115.068
C2 O1 C3 59.598 C2 C3 H6 119.128
C2 C3 H7 119.128 C3 C2 H4 119.128
C3 C2 H5 119.128 H4 C2 H5 115.999
H6 C3 H7 115.999
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability