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 C4H5N (Pyrrole)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.30456 0.30025 0.15117
Rotational Constants from 1966Herzberg
Calculated rotational constants for C4H5N (Pyrrole).

Point Group C2v

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
rCN 1.370 1 3 1969Nyg/Nie:491
rCC 1.382 3 5 1969Nyg/Nie:491
rCC 1.417 5 6 1969Nyg/Nie:491
rNH 0.996 1 2 1969Nyg/Nie:491
rCH 1.076 3 7 1969Nyg/Nie:491
aCNC 109.8 3 1 4 1969Nyg/Nie:491
aCCN 107.7 1 3 5 1969Nyg/Nie:491
aCCC 104.7 3 5 6 1969Nyg/Nie:491
aHCN 121.5 1 3 7 1969Nyg/Nie:491
aHCC 127.1 6 5 9 1969Nyg/Nie:491
aHNC 125.1 2 1 3 1969Nyg/Nie:491 by symmetry
aHCC 130.8 5 3 7 1969Nyg/Nie:491 by symmetry
aHCC 128.2 3 5 9 1969Nyg/Nie:491 by symmetry
picture of Pyrrole

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-N 2
C=C 2
C-C 1
H-N 1
H-C 4

Atom x (Å) y (Å) z (Å)
N1 0.0000 0.0000 1.1218
H2 0.0000 0.0000 2.1178
C3 0.0000 1.1209 0.3341
C4 0.0000 -1.1209 0.3341
C5 0.0000 0.7076 -0.9847
C6 0.0000 -0.7076 -0.9847
H7 0.0000 2.1084 0.7614
H8 0.0000 -2.1084 0.7614
H9 0.0000 1.3566 -1.8429
H10 0.0000 -1.3566 -1.8429

Atom - Atom Distances (Å)

  N1 H2 C3 C4 C5 C6 H7 H8 H9 H10

Calculated geometries for C4H5N (Pyrrole).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
1969Nyg/Nie:491 Nygaard, Nielsen, Kirchheiner, Maltesen, Rastrup-Andersen, Sorensen, Microwave Spectra of Isotopic Pyrroles. Molecular Structure, Dipole Moment, and 14N Quadrupole Coupling Constants of Pyrrole, J. Mol. Sturct., Vole 3, pgs. 491-506 10.1016/0022-2860(69)80031-1

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