return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C2H2O (Oxirene)

using model chemistry: CCSD(T)/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)/cc-pVTZ
 hartrees
Energy at 0K-152.232256
Energy at 298.15K 
HF Energy-151.641663
Nuclear repulsion energy61.171544
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)/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 3406 3320        
2 A1 1761 1717        
3 A1 1076 1049        
4 A1 875 853        
5 A2 569 555        
6 B1 493 481        
7 B2 3335 3251        
8 B2 961 937        
9 B2 142 139        

Unscaled Zero Point Vibrational Energy (zpe) 6308.9 cm-1
Scaled (by 0.9748) Zero Point Vibrational Energy (zpe) 6149.9 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 CCSD(T)/cc-pVTZ
ABC
1.10457 0.87585 0.48850

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 0.896
C2 0.000 0.637 -0.464
C3 0.000 -0.637 -0.464
H4 0.000 1.654 -0.798
H5 0.000 -1.654 -0.798

Atom - Atom Distances (Å)
  O1 C2 C3 H4 H5
O11.50251.50252.36752.3675
C21.50251.27471.06972.3153
C31.50251.27472.31531.0697
H42.36751.06972.31533.3075
H52.36752.31531.06973.3075

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 133.265
O1 C3 C2 64.900 O1 C3 H5 133.265
C2 O1 C3 50.199 C2 C3 H5 161.835
C3 C2 H4 161.835
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability