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

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

Isomers of B2H4

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a HBHHBH 9000348 Diborane(4) C2V   sketch of Diborane(4) C2V
b B2H4 18099451 Diborane(4) D2d   sketch of Diborane(4) D2d
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**
hartree fock HF   0.0 a
-80.8 b
density functional TPSSh   0.0 a
-10.9 b
Moller Plesset perturbation MP3=FULL 0.0 a
-21.5 b
0.0 a
-16.0 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.