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IV.A.4. (XIV.F.)

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

Isomers of C9H8

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C9H8 14867835 sprio[4.4]nona-1,3,6,8-tetraene   sketch of sprio[4.4]nona-1,3,6,8-tetraene
b C9H8 95136 Indene 0.0 sketch of Indene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1 196.3 a
0.0 b
PM3 164.3 a
0.0 b
PM6 150.9 a
0.0 b
composite G1 164.0 a
0.0 b
G2MP2 160.7 a
0.0 b
G2 160.4 a
0.0 b
G3 165.9 a
0.0 b
G3B3 162.4 a
0.0 b
CBS-Q 209.0 a
0.0 b

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 III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.