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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: QCISD(T)=FULL/Def2TZVPP

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)=FULL/Def2TZVPP
 hartrees
Energy at 0K-152.296334
Energy at 298.15K 
HF Energy-151.649013
Nuclear repulsion energy61.271930
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)=FULL/Def2TZVPP
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 A1 3410 3410        
2 A1 1757 1757        
3 A1 1075 1075        
4 A1 878 878        
5 A2 590 590        
6 B1 512 512        
7 B2 3339 3339        
8 B2 952 952        
9 B2 150 150        

Unscaled Zero Point Vibrational Energy (zpe) 6331.9 cm-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 6331.9 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)=FULL/Def2TZVPP
ABC
1.10771 0.87909 0.49012

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD(T)=FULL/Def2TZVPP

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.894
C2 0.000 0.636 -0.464
C3 0.000 -0.636 -0.464
H4 0.000 1.652 -0.794
H5 0.000 -1.652 -0.794

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50021.50022.36182.3618
C21.50021.27271.06762.3118
C31.50021.27272.31181.0676
H42.36181.06762.31183.3035
H52.36182.31181.06763.3035

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.900 O1 C2 H4 133.083
O1 C3 C2 64.900 O1 C3 H5 133.083
C2 O1 C3 50.199 C2 C3 H5 162.016
C3 C2 H4 162.016
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability