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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: QCISD(T)/cc-pVDZ

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(T)/cc-pVDZ
 hartrees
Energy at 0K-152.076507
Energy at 298.15K 
HF Energy-151.589733
Nuclear repulsion energy60.466548
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(T)/cc-pVDZ
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 3394 3235        
2 A1 1744 1662        
3 A1 1059 1009        
4 A1 845 805        
5 A2 495 472        
6 B1 453 432        
7 B2 3330 3174        
8 B2 919 876        
9 B2 244i 233i        

Unscaled Zero Point Vibrational Energy (zpe) 5997.1 cm-1
Scaled (by 0.9531) Zero Point Vibrational Energy (zpe) 5715.9 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 QCISD(T)/cc-pVDZ
ABC
1.07249 0.86136 0.47770

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD(T)/cc-pVDZ

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.904
C2 0.000 0.647 -0.468
C3 0.000 -0.647 -0.468
H4 0.000 1.677 -0.809
H5 0.000 -1.677 -0.809

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.51641.51642.39722.3972
C21.51641.29421.08512.3491
C31.51641.29422.34911.0851
H42.39721.08512.34913.3541
H52.39722.34911.08513.3541

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.739 O1 C2 H4 133.611
O1 C3 C2 64.739 O1 C3 H5 133.611
C2 O1 C3 50.521 C2 C3 H5 161.650
C3 C2 H4 161.650
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability