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

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

Isomers of C2H5O

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH2CH2OH 4422542 2-hydroxy ethyl radical   sketch of 2-hydroxy ethyl radical
b CH3OCH2 16520040 methoxymethyl radical   sketch of methoxymethyl radical
c CH3CH2O 2154509 Ethoxy radical 0.0 sketch of Ethoxy radical
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM6 210.6 a
67.2 b
composite G1 -9.1 a
-169.5 b
0.0 c
G2MP2 -12.3 a
-172.8 b
0.0 c
G2 -10.2 a
-170.3 b
0.0 c
G3 -11.6 a
-168.6 b
0.0 c
G3B3 164.0 a
22.7 b
0.0 c
G4 164.1 a
23.1 b
0.0 c
CBS-Q 173.0 a
14.6 b
0.0 c

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.