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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-29.222769
Energy at 298.15K-29.226685
HF Energy-28.916589
Nuclear repulsion energy38.342920
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' 3114 3039 19.94 45.73 0.75 0.86
2 A' 2975 2903 14.46 198.53 0.01 0.02
3 A' 2951 2880 110.17 109.11 0.52 0.69
4 A' 1593 1555 60.64 2.13 0.71 0.83
5 A' 1501 1465 33.34 17.80 0.69 0.82
6 A' 1442 1407 21.26 4.42 0.44 0.61
7 A' 1414 1380 3.60 14.91 0.55 0.71
8 A' 1152 1124 21.50 5.24 0.38 0.55
9 A' 900 879 5.60 9.45 0.33 0.49
10 A' 495 483 12.65 2.42 0.48 0.65
11 A" 3070 2996 20.89 63.87 0.75 0.86
12 A" 1496 1460 13.83 12.94 0.75 0.86
13 A" 1142 1115 0.22 0.20 0.75 0.86
14 A" 787 768 1.74 8.41 0.75 0.86
15 A" 152 148 0.95 0.99 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 12091.0 cm-1
Scaled (by 0.976) Zero Point Vibrational Energy (zpe) 11800.8 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
1.79695 0.32011 0.28648

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 0.480 0.000
C2 -0.994 -0.688 0.000
O3 1.265 0.330 0.000
H4 -0.431 1.504 0.000
H5 -0.446 -1.642 0.000
H6 -1.643 -0.629 0.891
H7 -1.643 -0.629 -0.891

Atom - Atom Distances (Å)
  C1 C2 O3 H4 H5 H6 H7
C11.53361.27431.11072.16812.17302.1730
C21.53362.47802.26281.09921.10391.1039
O31.27432.47802.06292.61143.18923.1892
H41.11072.26282.06293.14532.60942.6094
H52.16811.09922.61143.14531.80271.8027
H62.17301.10393.18922.60941.80271.7817
H72.17301.10393.18922.60941.80271.7817

picture of Acetaldehyde state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H5 109.777 C1 C2 H6 109.880
C1 C2 H7 109.880 C2 C1 O3 123.632
C2 C1 H4 116.777 O3 C1 H4 119.591
H5 C2 H6 109.830 H5 C2 H7 109.830
H6 C2 H7 107.614
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability