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All results from a given calculation for CH3CHO (Acetaldehyde)

using model chemistry: CID/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at CID/3-21G*
 hartrees
Energy at 0K-152.348164
Energy at 298.15K 
HF Energy-152.054029
Nuclear repulsion energy68.956710
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 CID/3-21G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A' 3207 2984 9.58      
2 A' 3104 2888 1.74      
3 A' 3015 2805 103.58      
4 A' 1788 1664 66.62      
5 A' 1574 1465 18.44      
6 A' 1504 1399 4.21      
7 A' 1483 1380 27.97      
8 A' 1166 1085 27.11      
9 A' 902 839 9.50      
10 A' 506 471 12.61      
11 A" 3160 2940 8.44      
12 A" 1586 1476 12.44      
13 A" 1201 1118 0.56      
14 A" 842 783 2.27      
15 A" 169 157 0.49      

Unscaled Zero Point Vibrational Energy (zpe) 12603.2 cm-1
Scaled (by 0.9305) Zero Point Vibrational Energy (zpe) 11727.3 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 CID/3-21G*
ABC
1.88614 0.32964 0.29618

See section I.F.4 to change rotational constant units
Geometric Data calculated at CID/3-21G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.468 0.000
C2 -0.956 -0.714 0.000
O3 1.227 0.378 0.000
H4 -0.499 1.448 0.000
H5 -0.384 -1.643 0.000
H6 -1.598 -0.673 0.885
H7 -1.598 -0.673 -0.885

Atom - Atom Distances (Å)
  C1 C2 O3 H4 H5 H6 H7
C11.51971.22991.10032.14492.15402.1540
C21.51972.44002.21011.09041.09481.0948
O31.22992.44002.03072.58373.14133.1413
H41.10032.21012.03073.09312.54812.5481
H52.14491.09042.58373.09311.78841.7884
H62.15401.09483.14132.54811.78841.7707
H72.15401.09483.14132.54811.78841.7707

picture of Acetaldehyde state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H5 109.425 C1 C2 H6 109.880
C1 C2 H7 109.880 C2 C1 O3 124.764
C2 C1 H4 114.075 O3 C1 H4 121.161
H5 C2 H6 109.854 H5 C2 H7 109.854
H6 C2 H7 107.929
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability