National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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

Listing of experimental geometry data for HClO4 (perchloric acid)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.18571 0.17730 0.17461
Rotational Constants from 1994Cas/Mac:8339
Calculated rotational constants for HClO4 (perchloric acid).

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
rOCl 1.404 1 4 1994Cas/Mac:8339 ra
rOCl 1.414 1 2 1994Cas/Mac:8339 ra
rOCl 1.641 1 3 1994Cas/Mac:8339 ra
rOH 0.980 3 6 1994Cas/Mac:8339 MP2/6-31G** value
aOClO 115 3 1 4 1994Cas/Mac:8339
aOClO 114.6 4 1 5 1994Cas/Mac:8339
aOClO 101.5 2 1 3 1994Cas/Mac:8339
aOClO 104.2 2 1 4 1994Cas/Mac:8339
aHOCl 105 1 2 6 1994Cas/Mac:8339 MP2/6-31G** value
picture of perchloric acid

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-O 1
O-Cl 1
O=Cl 3

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)


Calculated geometries for HClO4 (perchloric acid).
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squib reference DOI
1994Cas/Mac:8339 B Casper, H-G Mack, HSP Muller, H Willner, H Oberhammer "Molecular Structures of Perchloric Acid and Halogen Perhclorates ClOClO3 and FOClO3" J. Phys. Chem. 1994, 90, 8339-8342 10.1021/j100085a013

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