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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: HF/cc-pVTZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at HF/cc-pVTZ
 hartrees
Energy at 0K-151.645357
Energy at 298.15K 
HF Energy-151.645357
Nuclear repulsion energy62.769259
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 HF/cc-pVTZ
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 3569 3248 2.68 62.19 0.22 0.35
2 A1 1976 1799 2.30 95.42 0.15 0.26
3 A1 1173 1068 15.28 6.97 0.56 0.72
4 A1 998 908 79.37 9.32 0.71 0.83
5 A2 824 750 0.00 8.95 0.75 0.86
6 B1 690 628 98.38 0.09 0.75 0.86
7 B2 3484 3171 59.35 14.70 0.75 0.86
8 B2 1107 1007 5.06 2.06 0.75 0.86
9 B2 446 406 4.78 11.09 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 7133.2 cm-1
Scaled (by 0.9101) Zero Point Vibrational Energy (zpe) 6491.9 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 HF/cc-pVTZ
ABC
1.15584 0.92901 0.51504

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/cc-pVTZ

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.870
C2 0.000 0.620 -0.452
C3 0.000 -0.620 -0.452
H4 0.000 1.631 -0.770
H5 0.000 -1.631 -0.770

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.46001.46002.31282.3128
C21.46001.24001.05962.2730
C31.46001.24002.27301.0596
H42.31281.05962.27303.2612
H52.31282.27301.05963.2612

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.871 O1 C2 H4 132.614
O1 C3 C2 64.871 O1 C3 H5 132.614
C2 O1 C3 50.258 C2 C3 H5 162.515
C3 C2 H4 162.515
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/cc-pVTZ Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 O -0.378      
2 C 0.007      
3 C 0.007      
4 H 0.182      
5 H 0.182      


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 -2.561 2.561
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -18.574 0.000 0.000
y 0.000 -11.421 0.000
z 0.000 0.000 -18.880
Traceless
 xyz
x -3.424 0.000 0.000
y 0.000 7.306 0.000
z 0.000 0.000 -3.882
Polar
3z2-r2-7.764
x2-y2-7.153
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.221 0.000 0.000
y 0.000 4.512 0.000
z 0.000 0.000 3.158


<r2> (average value of r2) Å2
<r2> 29.797
(<r2>)1/2 5.459