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All results from a given calculation for C2H4 (Ethylene)

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 D2H 1Ag
Energy calculated at QCISD/3-21G*
 hartrees
Energy at 0K-77.808555
Energy at 298.15K-77.811741
HF Energy-77.599122
Nuclear repulsion energy33.118094
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 Ag 3133 3011 0.00      
2 Ag 1682 1616 0.00      
3 Ag 1411 1356 0.00      
4 Au 1052 1012 0.00      
5 B1u 3113 2992 14.49      
6 B1u 1548 1488 4.94      
7 B2g 961 923 0.00      
8 B2u 3210 3085 30.73      
9 B2u 882 848 1.36      
10 B3g 3181 3058 0.00      
11 B3g 1286 1236 0.00      
12 B3u 979 941 93.55      

Unscaled Zero Point Vibrational Energy (zpe) 11219.4 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 10783.0 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
4.89141 0.98407 0.81925

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

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.672
C2 0.000 0.000 -0.672
H3 0.000 0.925 1.249
H4 0.000 -0.925 1.249
H5 0.000 -0.925 -1.249
H6 0.000 0.925 -1.249

Atom - Atom Distances (Å)
  C1 C2 H3 H4 H5 H6
C11.34411.09001.09002.13222.1322
C21.34412.13222.13221.09001.0900
H31.09002.13221.84923.10842.4985
H41.09002.13221.84922.49853.1084
H52.13221.09003.10842.49851.8492
H62.13221.09002.49853.10841.8492

picture of Ethylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H5 121.976 C1 C2 H6 121.976
C2 C1 H3 121.976 C2 C1 H4 121.976
H3 C1 H4 116.048 H5 C2 H6 116.048
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability