return to home page

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

Listing of experimental geometry data for C2H2O4 (Oxalic Acid)

No experimental rotational constants available.
Calculated rotational constants for C2H2O4 (Oxalic Acid).

Point Group C2h

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 1.544 1 2 1976Hellwege(II/7)
rCO 1.205 1 5 1976Hellwege(II/7)
rCO 1.336 1 3 1976Hellwege(II/7)
aCCO 123.1 1 2 6 1976Hellwege(II/7)
aOCO 125 3 1 5 1976Hellwege(II/7)
aCOH 104.4 1 3 7 1976Hellwege(II/7)
picture of Oxalic Acid

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-O 2
C=O 2
H-O 2

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)

Calculated geometries for C2H2O4 (Oxalic Acid).

By selecting the following links, you may be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to
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.  

Got a better number? Please email us at