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II.A.3. (XII.A.1.)

Listing of experimental geometry data for CH3CH2CHO (Propanal)

Rotational Constants (cm-1)
See section I.F.4 to change rotational constant units
0.87063 0.13712 0.13218
Rotational Constants from 1988Ran/Har:1199
Calculated rotational constants for CH3CH2CHO (Propanal).

Point Group Cs

Internal coordinates (distances (r) in Å) (angles (a) in degrees) (dihedrals (d) in degrees)
Description Value Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rCC 1.523 1 2 1992Kuchitsu(II/21) CH3-CH2
rCH 1.103 1 6 1992Kuchitsu(II/21) out of plane, end C
rCH 1.096 1 5 1992Kuchitsu(II/21) in plane, end C
rCH 1.105 2 8 1992Kuchitsu(II/21) middle C
rCC 1.509 2 3 1992Kuchitsu(II/21) C with =O
rCO 1.210 3 4 1992Kuchitsu(II/21)
rCH 1.115 3 10 1992Kuchitsu(II/21) C with =O
aHCH 108.7 5 1 6 1992Kuchitsu(II/21) in to out
aHCC 110.3 2 1 6 1992Kuchitsu(II/21) to end CH3
aHCH 107 6 1 7 1992Kuchitsu(II/21) out to out
aHCC 111.9 3 2 8 1992Kuchitsu(II/21)
aCCC 113.8 1 2 3 1992Kuchitsu(II/21)
aHCH 105 8 2 9 1992Kuchitsu(II/21)
aCCO 124.4 2 3 4 1992Kuchitsu(II/21)
aHCC 115.1 2 3 10 1992Kuchitsu(II/21) to C with =O
aHCO 120.5 4 3 10 1992Kuchitsu(II/21) from symmetry
aHCC 111.7 2 1 5 1992Kuchitsu(II/21) from symmetry
aHCC 106.8 1 2 8 by symmetry
picture of Propanal

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 6
C-C 2
C=O 1

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)

Calculated geometries for CH3CH2CHO (Propanal).

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squib reference DOI
1988Ran/Har:1199 J Randell JA Hardy, AP Cox, "The microwave spectrum and potential function of propanal" J. Chem. Soc. Farad. Trans. 2 1988, 84(8), 1199-1212 10.1039/f29888401199
1992Kuchitsu(II/21) Kuchitsu (ed.), Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 21: Structure Data of Free Polyatomic Molecules. Springer-Verlag, Berlin, 1992.  

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