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

Relative enthalpies of isomers - Comparison of 0K enthalpies (kJ mol-1)

Isomers of C2Cl2F4

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CF2ClCF2Cl 76142 1,2-Dichloro-1,1,2,2-tetrafluoroethane   sketch of 1,2-Dichloro-1,1,2,2-tetrafluoroethane
b CF3CFCl2 374072 1,1-Dichlorotetrafluoroethane   sketch of 1,1-Dichlorotetrafluoroethane
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets

Methods with standard basis sets
6-31G* 6-31+G** TZVP
hartree fock HF     0.0 a
-11.7 b
density functional B3LYP     0.0 a
-6.0 b
TPSSh   0.0 a
-5.9 b
 
Moller Plesset perturbation MP2     0.0 a
-10.8 b
MP3=FULL 0.0 a
-10.8 b
0.0 a
-5.8 b
 
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.