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

using model chemistry: QCISD/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 QCISD/3-21G
 hartrees
Energy at 0K-152.329458
Energy at 298.15K 
HF Energy-151.997169
Nuclear repulsion energy72.493727
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 QCISD/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 3127 3031 2.88      
2 A1 1582 1533 0.03      
3 A1 1208 1170 6.18      
4 A1 1129 1094 4.24      
5 A1 800 775 18.64      
6 A2 3199 3101 0.00      
7 A2 1203 1166 0.00      
8 A2 1001 970 0.00      
9 B1 3218 3118 40.12      
10 B1 1113 1079 1.09      
11 B1 847 821 0.06      
12 B2 3116 3020 20.02      
13 B2 1565 1517 0.22      
14 B2 1136 1101 13.78      
15 B2 759 735 2.15      

Unscaled Zero Point Vibrational Energy (zpe) 12501.0 cm-1
Scaled (by 0.9692) Zero Point Vibrational Energy (zpe) 12116.0 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 QCISD/3-21G
ABC
0.75801 0.71639 0.43330

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.918
C2 0.000 0.750 -0.402
C3 0.000 -0.750 -0.402
H4 0.923 1.279 -0.631
H5 -0.923 1.279 -0.631
H6 -0.923 -1.279 -0.631
H7 0.923 -1.279 -0.631

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5 H6 H7
O11.51761.51762.21062.21062.21062.2106
C21.51761.50011.08831.08832.24102.2410
C31.51761.50012.24102.24101.08831.0883
H42.21061.08832.24101.84563.15472.5585
H52.21061.08832.24101.84562.55853.1547
H62.21062.24101.08833.15472.55851.8456
H72.21062.24101.08832.55853.15471.8456

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 60.382 O1 C2 H4 115.067
O1 C2 H5 115.067 O1 C3 C2 60.382
O1 C3 H6 115.067 O1 C3 H7 115.067
C2 O1 C3 59.235 C2 C3 H6 119.099
C2 C3 H7 119.099 C3 C2 H4 119.099
C3 C2 H5 119.099 H4 C2 H5 115.978
H6 C3 H7 115.978
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability