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

Listing of experimental geometry data for C3H4O (Methylketene)

Rotational Constants (cm-1)
See section I.F.4 to change rotational constant units
1.29823 0.15035 0.13799
Rotational Constants from 1966Bak/Chr:883
Calculated rotational constants for C3H4O (Methylketene).

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
rCO 1.171 1 4 1966Bak/Chr:883
rCC 1.306 1 2 1966Bak/Chr:883
rCC 1.518 2 3 1966Bak/Chr:883
rCH 1.083 2 5 1966Bak/Chr:883 vinyl
rCH 1.083 3 6 1966Bak/Chr:883 methyl
aCCO 180 2 1 4 1966Bak/Chr:883
aCCC 122.6 1 2 3 1966Bak/Chr:883
aHCC 113.7 1 2 5 1966Bak/Chr:883
aHCH 109.9 6 3 7 1966Bak/Chr:883
picture of Methylketene

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-C 1
C=C 1
C=O 1
H-C 4

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)

Calculated geometries for C3H4O (Methylketene).

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squib reference DOI
1966Bak/Chr:883 B Bak, JJ Christiansen, K Kuntsmann, L Nygaard, J Rastrup-Andersen "Microwave Spectrum, Molecular Structure, Barrier to Internal Rotation, and Dipole Moment of Methylketene" J. Chem. Phys. 45(1), 883, 1966 10.1063/1.1727700

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