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All results from a given calculation for C2H2O (Oxirene)

using model chemistry: QCISD(T)/aug-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)/aug-cc-pVDZ
 hartrees
Energy at 0K-152.114828
Energy at 298.15K 
HF Energy-151.603063
Nuclear repulsion energy60.240223
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)/aug-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 3384 3308        
2 A1 1733 1695        
3 A1 1032 1009        
4 A1 840 821        
5 A2 446 436        
6 B1 449 439        
7 B2 3318 3244        
8 B2 917 897        
9 B2 97i 95i        

Unscaled Zero Point Vibrational Energy (zpe) 6010.6 cm-1
Scaled (by 0.9778) Zero Point Vibrational Energy (zpe) 5877.2 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 QCISD(T)/aug-cc-pVDZ
ABC
1.07218 0.84846 0.47365

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.911
C2 0.000 0.647 -0.472
C3 0.000 -0.647 -0.472
H4 0.000 1.677 -0.811
H5 0.000 -1.677 -0.811

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.52641.52642.40342.4034
C21.52641.29461.08402.3487
C31.52641.29462.34871.0840
H42.40341.08402.34873.3534
H52.40342.34871.08403.3534

picture of Oxirene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 C2 C3 64.908 O1 C2 H4 133.350
O1 C3 C2 64.908 O1 C3 H5 133.350
C2 O1 C3 50.185 C2 C3 H5 161.743
C3 C2 H4 161.743
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability