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Relative enthalpies of isomers - Comparison of 298.15K enthalpies (kJ mol-1)

Isomers of C4H6N

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C4H6N+ 9000911 pyrrole, protonated   sketch of pyrrole, protonated
b C4H6N+ 910095135 pyrrole, beta-protonated   sketch of pyrrole, beta-protonated
c C4H6N+ 910095204 pyrrole, alpha-protonated   sketch of pyrrole, alpha-protonated
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1 1142.3 a
1083.4 b
1086.4 c
PM3 1092.3 a
1049.4 b
1056.4 c
PM6 1051.3 a
1015.8 b
1025.6 c
composite G1 NC
NC
NC
G2MP2 NC
NC
NC
G2 NC
NC
NC
G3 NC
NC
NC
G3B3 NC
NC
NC
G4 NC
NC
NC
CBS-Q NC
NC
NC

Methods with standard basis sets
NC = not calculated
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.
gaw refers to the group additivity method implemeted in the NIST Chemistry Webbook.
See section Calculated; Vibrations; Scale Factors; Scale factors to list vibrational scaling factors.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to calculate a vibrational scaling factor for a given set of molecules.