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All results from a given calculation for CH3CHO (Acetaldehyde)

using model chemistry: MP2/CEP-121G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP2/CEP-121G*
 hartrees
Energy at 0K-29.435565
Energy at 298.15K-29.439460
HF Energy-28.994952
Nuclear repulsion energy39.018361
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 MP2/CEP-121G*
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 3055 10.30 47.40 0.74 0.85
2 A' 3068 2923 4.54 148.72 0.01 0.02
3 A' 2978 2837 126.92 150.13 0.33 0.50
4 A' 1738 1656 120.08 6.37 0.65 0.79
5 A' 1505 1434 24.10 15.09 0.66 0.80
6 A' 1440 1372 17.87 9.67 0.37 0.54
7 A' 1415 1348 11.99 3.72 0.74 0.85
8 A' 1151 1097 21.02 3.60 0.32 0.48
9 A' 901 859 6.10 7.41 0.37 0.54
10 A' 503 480 12.71 1.65 0.44 0.61
11 A" 3157 3008 11.20 61.88 0.75 0.86
12 A" 1507 1436 12.71 9.97 0.75 0.86
13 A" 1145 1091 0.01 0.70 0.75 0.86
14 A" 780 743 0.89 7.49 0.75 0.86
15 A" 144 138 0.86 0.96 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 12319.4 cm-1
Scaled (by 0.9528) Zero Point Vibrational Energy (zpe) 11737.9 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 MP2/CEP-121G*
ABC
1.86155 0.33165 0.29711

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/CEP-121G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.469 0.000
C2 -0.957 -0.707 0.000
O3 1.227 0.362 0.000
H4 -0.469 1.476 0.000
H5 -0.397 -1.643 0.000
H6 -1.604 -0.651 0.883
H7 -1.604 -0.651 -0.883

Atom - Atom Distances (Å)
  C1 C2 O3 H4 H5 H6 H7
C11.51641.23191.11012.14982.14682.1468
C21.51642.43192.23631.09141.09631.0963
O31.23192.43192.02902.58073.13413.1341
H41.11012.23632.02903.11982.56752.5675
H52.14981.09142.58073.11981.79481.7948
H62.14681.09633.13412.56751.79481.7669
H72.14681.09633.13412.56751.79481.7669

picture of Acetaldehyde state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H5 109.977 C1 C2 H6 109.455
C1 C2 H7 109.455 C2 C1 O3 124.143
C2 C1 H4 115.872 O3 C1 H4 119.985
H5 C2 H6 110.259 H5 C2 H7 110.259
H6 C2 H7 107.390
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability