National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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 NH3 (Ammonia)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
9.44430 9.44430 6.19600
Rotational Constants from 1966Herzberg
Calculated rotational constants for NH3 (Ammonia).

Point Group C3v

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
rNH 1.012 1 2 1966Herzberg
aHNH 106.67 2 1 3 1966Herzberg
aXNH 112.15 255 1 2 1966Herzberg from symmetry. X is on symmetry axis.
picture of Ammonia

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
N1 0.0000 0.0000 0.0000
H2 0.0000 -0.9377 -0.3816
H3 0.8121 0.4689 -0.3816
H4 -0.8121 0.4689 -0.3816

Atom - Atom Distances (Å)

  N1 H2 H3 H4

Calculated geometries for NH3 (Ammonia).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  

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