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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: CCSD(T)=FULL/TZVP

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/TZVP
 hartrees
Energy at 0K-152.201988
Energy at 298.15K 
HF Energy-151.636761
Nuclear repulsion energy61.114040
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/TZVP
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 3421 3271        
2 A1 1771 1693        
3 A1 1079 1032        
4 A1 873 834        
5 A2 434 414        
6 B1 465 445        
7 B2 3353 3206        
8 B2 959 917        
9 B2 49i 47i        

Unscaled Zero Point Vibrational Energy (zpe) 6152.9 cm-1
Scaled (by 0.956) Zero Point Vibrational Energy (zpe) 5882.2 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/TZVP
ABC
1.10598 0.87142 0.48740

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.898
C2 0.000 0.637 -0.465
C3 0.000 -0.637 -0.465
H4 0.000 1.653 -0.801
H5 0.000 -1.653 -0.801

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50531.50532.37082.3708
C21.50531.27381.07012.3143
C31.50531.27382.31431.0701
H42.37081.07012.31433.3059
H52.37082.31431.07013.3059

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.970 O1 C2 H4 133.307
O1 C3 C2 64.970 O1 C3 H5 133.307
C2 O1 C3 50.060 C2 C3 H5 161.724
C3 C2 H4 161.724
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability