return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Energy > Similar molecules > Isomers OR FAQ Help > List > Similar molecules > Isomers

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 CH3CHOH+ 2348461 acetaldehyde, protonated   sketch of acetaldehyde, protonated
b C2H4OH+ 9000915 ethylene oxide, protonated   sketch of ethylene oxide, protonated
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical AM1
757.2 b
PM3
809.7 b
PM6
712.8 b
composite G1 NC
NC
G2MP2 NC
NC
G2 NC
NC
G3 NC
NC
G3B3 NC
NC
G4 NC
NC
CBS-Q NC
NC

Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
hartree fock HF NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
density functional LSDA NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
BLYP NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
B1B95 NC NC NC NC NC NC NC NC NC NC NC NC NC NC  
B3LYP NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
B3LYPultrafine   NC     NC NC NC NC     NC NC NC NC NC
B3PW91 NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
mPW1PW91 NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
M06-2X NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
PBEPBE NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
PBEPBEultrafine   NC     NC NC NC NC     NC NC NC NC NC
PBE1PBE NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
HSEh1PBE NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
TPSSh NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
wB97X-D NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
Moller Plesset perturbation MP2 NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
MP2=FULL NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
MP3         NC   NC       NC NC NC    
MP3=FULL   NC NC NC NC NC NC NC NC NC NC NC NC NC NC
MP4   NC     NC       NC   NC NC NC NC NC
MP4=FULL   NC     NC       NC     NC NC NC NC
B2PLYP NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
B2PLYP=FULL NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC
Configuration interaction CID   NC NC NC NC     NC              
CISD   NC NC NC NC     NC              
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
Quadratic configuration interaction QCISD   NC NC NC NC NC NC NC NC NC NC NC NC NC NC
QCISD(T)         NC     NC     NC NC NC NC NC
QCISD(T)=FULL         NC   NC         NC NC NC NC
Coupled Cluster CCD   NC NC NC NC NC NC NC NC NC NC NC NC NC  
CCSD         NC         NC NC NC NC NC  
CCSD=FULL         NC         NC NC NC NC NC  
CCSD(T)         NC NC   NC     NC NC NC NC NC
CCSD(T)=FULL         NC           NC NC NC NC NC
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF -76549.6 a -76745.8 a -76567.4 a -76767.5 a NC NC      
density functional B3LYP -78404.3 a -78535.2 a -78422.9 a -78559.3 a NC NC      
wB97X-D -78415.7 a -78552.5 a -78433.6 a -78575.3 a NC NC      
Moller Plesset perturbation MP2 -77226.2 a -77794.8 a -77323.2 a -77890.2 a NC NC      
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.