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Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
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XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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

Listing of experimental geometry data for CHOCHCHCH3 (2-Butenal)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
Rotational Constants from
Calculated rotational constants for CHOCHCHCH3 (2-Butenal).

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 1.470 3 4 1976Hellwege(II/7) !assumed, from C=O
rCC 1.345 2 3 1976Hellwege(II/7) !assumed
rCC 1.501 1 2 1976Hellwege(II/7) !assumed, to end
rCO 1.219 4 5 1976Hellwege(II/7) !assumed
rCH 1.108 4 6 1976Hellwege(II/7) !assumed, C with =O
rCH 1.086 2 8 1976Hellwege(II/7) !assumed, C with =C away from O
rCH 1.084 3 7 1976Hellwege(II/7) !assumed, C with =C towards O
rCH 1.090 1 9 1976Hellwege(II/7) !assumed, end C
aCCC 119.83 2 3 4 1976Hellwege(II/7) !assumed, towards =O
aCCO 123.28 3 4 5 1976Hellwege(II/7) !assumed
aHCC 115.1 3 4 6 1976Hellwege(II/7) !assumed, middle C has =O
aHCH 109.47 9 1 10 1976Hellwege(II/7) !assumed, end C
aHCC 109.47 2 1 9 1976Hellwege(II/7) !assumed, towards end C
aHCC 122.83 2 3 7 1976Hellwege(II/7) !assumed
aCCC 125.64 2 3 4 1976Hellwege(II/7)
aHCC 116.09 3 4 6 1976Hellwege(II/7)
dHCCH 120.5 9 1 2 10 from HF/6-31G*
picture of 2-Butenal

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=C 1
C=O 1

Atom x (Å) y (Å) z (Å)
C1 2.3582 -0.5752 0.0000
C2 0.8612 -0.6845 0.0000
C3 0.0000 0.3486 0.0000
C4 -1.4477 0.0937 0.0000
O5 -2.2832 0.9813 0.0000
H6 -1.7366 -0.9760 0.0000
H7 0.3239 1.3851 0.0000
H8 0.5379 -1.7192 0.0000
H9 2.7651 0.4360 0.0000
H10 2.8725 -1.0359 0.8435
H11 2.8725 -1.0359 -0.8435

Atom - Atom Distances (Å)

  C1 C2 C3 C4 O5 H6 H7 H8 H9 H10 H11

Calculated geometries for CHOCHCHCH3 (2-Butenal).
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squib reference DOI
1976Hellwege(II/7) Hellwege, KH and AM Hellwege (ed.). Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 7: Structure Data of Free Polyatomic Molecules. Springer-Verlag. Berlin. 1976.  

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