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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: PBEPBE/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 PBEPBE/3-21G
 hartrees
Energy at 0K-151.441110
Energy at 298.15K 
HF Energy-151.441110
Nuclear repulsion energy58.932481
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 PBEPBE/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 3336 3305 3.23 86.98 0.18 0.30
2 A1 1740 1724 0.83 38.59 0.25 0.39
3 A1 1001 992 2.12 3.80 0.44 0.61
4 A1 821 814 20.95 7.63 0.53 0.69
5 A2 584 579 0.00 2.64 0.75 0.86
6 B1 538 533 111.73 0.97 0.75 0.86
7 B2 3262 3232 31.11 20.30 0.75 0.86
8 B2 882 874 10.60 3.54 0.75 0.86
9 B2 379i 376i 5.57 14.43 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 5892.3 cm-1
Scaled (by 0.9909) Zero Point Vibrational Energy (zpe) 5838.7 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 PBEPBE/3-21G
ABC
1.09393 0.76087 0.44875

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.962
C2 0.000 0.642 -0.496
C3 0.000 -0.642 -0.496
H4 0.000 1.653 -0.870
H5 0.000 -1.653 -0.870

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.59311.59312.46732.4673
C21.59311.28461.07772.3257
C31.59311.28462.32571.0777
H42.46731.07772.32573.3063
H52.46732.32571.07773.3063

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 66.222 O1 C2 H4 134.068
O1 C3 C2 66.222 O1 C3 H5 134.068
C2 O1 C3 47.556 C2 C3 H5 159.710
C3 C2 H4 159.710
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.368      
2 C -0.052      
3 C -0.052      
4 H 0.236      
5 H 0.236      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.000 0.000 -2.558 2.558
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -18.394 0.000 0.000
y 0.000 -11.915 0.000
z 0.000 0.000 -18.024
Traceless
 xyz
x -3.424 0.000 0.000
y 0.000 6.293 0.000
z 0.000 0.000 -2.869
Polar
3z2-r2-5.738
x2-y2-6.479
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 1.066 0.000 0.000
y 0.000 4.148 0.000
z 0.000 0.000 2.731


<r2> (average value of r2) Å2
<r2> 32.346
(<r2>)1/2 5.687