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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: CCSD(T)=FULL/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 CCSD(T)=FULL/cc-pVTZ
 hartrees
Energy at 0K-152.275861
Energy at 298.15K 
HF Energy-151.642603
Nuclear repulsion energy61.410246
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 CCSD(T)=FULL/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 3426 3282        
2 A1 1775 1701        
3 A1 1084 1039        
4 A1 885 848        
5 A2 567 543        
6 B1 498 477        
7 B2 3341 3201        
8 B2 965 924        
9 B2 143 137        

Unscaled Zero Point Vibrational Energy (zpe) 6342.0 cm-1
Scaled (by 0.958) Zero Point Vibrational Energy (zpe) 6075.7 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 CCSD(T)=FULL/cc-pVTZ
ABC
1.11267 0.88310 0.49234

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)=FULL/cc-pVTZ

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.892
C2 0.000 0.635 -0.462
C3 0.000 -0.635 -0.462
H4 0.000 1.647 -0.795
H5 0.000 -1.647 -0.795

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.49651.49652.35792.3579
C21.49651.27051.06482.3061
C31.49651.27052.30611.0648
H42.35791.06482.30613.2936
H52.35792.30611.06483.2936

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.882 O1 C2 H4 133.315
O1 C3 C2 64.882 O1 C3 H5 133.315
C2 O1 C3 50.235 C2 C3 H5 161.803
C3 C2 H4 161.803
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability