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Computational Chemistry Comparison and Benchmark DataBase
Release 22May 2022
NIST Standard Reference Database 101
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IV.A.4. (XIV.F.)

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

Isomers of C2H3O

index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a CH2CHO 4400015 Vinyloxy radical   sketch of Vinyloxy radical
b CH3CO 3170692 Acetyl radical 0.0 sketch of Acetyl radical
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
semi-empirical PM3 -68.6 a
0.0 b
composite G1 23.7 a
0.0 b
G2MP2 25.0 a
0.0 b
G2 24.5 a
0.0 b
G3 21.3 a
0.0 b
G3B3 22.2 a
0.0 b
G3MP2
0.0 b
G4 24.2 a
0.0 b
CBS-Q 23.6 a
0.0 b
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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ
hartree fock HF   a -38.1 a
0.0 b 		-38.1 a
0.0 b 		-47.6 a
0.0 b 		-11.3 a
0.0 b 		-11.9 a
0.0 b 		-10.9 a
0.0 b 		  a   a   a
0.0 b 		  a -9.0 a
0.0 b 		  a     a   a  
0.0 b 		-6.2 a
0.0 b
ROHF   14.5 a
0.0 b 		14.5 a
0.0 b 		0.9 a
0.0 b 		13.2 a
0.0 b 		12.6 a
0.0 b 		26.6 a
0.0 b 		15.7 a
0.0 b 		NC       14.5 a
0.0 b 		14.4 a
0.0 b 		NC NC NC NC
0.0 b 		 
density functional LSDA
0.0 b 		27.2 a
0.0 b 		27.3 a
0.0 b 		14.0 a
0.0 b 		27.8 a
0.0 b 		27.8 a
0.0 b 		29.0 a
0.0 b 		33.6 a
0.0 b 		32.6 a
0.0 b 		30.8 a
0.0 b 		    31.0 a
0.0 b 		31.4 a
0.0 b 		  29.3 a
0.0 b 		NC  
0.0 b 		 
BLYP
0.0 b 		  a   a   a 21.0 a
0.0 b 		  a   a   a 26.1 a
0.0 b 		  a       a   a        
0.0 b 		 
B1B95 52.8 a
0.0 b 		21.9 a
0.0 b 		21.9 a
0.0 b 		8.6 a
0.0 b 		18.3 a
0.0 b 		36.2 a
0.0 b 		25.2 a
0.0 b 		40.8 a
0.0 b 		28.7 a
0.0 b 		28.0 a
0.0 b 		    27.9 a
0.0 b 		19.9 a
0.0 b 		  18.7 a
0.0 b 		NC  
0.0 b 		 
B3LYP 47.5 a
0.0 b 		17.3 a
0.0 b 		17.3 a
0.0 b 		3.4 a
0.0 b 		18.9 a
0.0 b 		18.7 a
0.0 b 		18.8 a
0.0 b 		24.0 a
0.0 b 		23.2 a
0.0 b 		21.8 a
0.0 b
0.0 b 		20.0 a
0.0 b 		21.8 a
0.0 b 		21.4 a
0.0 b 		NC 19.6 a
0.0 b 		21.1 a
0.0 b 		NC
0.0 b 		 
B3LYPultrafine         18.9 a
0.0 b 		 
0.0 b 		           
0.0 b 		    21.1 a
0.0 b 		     
B3PW91 46.0 a
0.0 b 		17.7 a
0.0 b 		17.7 a
0.0 b 		4.1 a
0.0 b 		19.7 a
0.0 b 		19.6 a
0.0 b 		19.7 a
0.0 b 		23.9 a
0.0 b 		23.1 a
0.0 b 		22.3 a
0.0 b 		    22.1 a
0.0 b 		22.0 a
0.0 b 		 
0.0 b 		   
0.0 b 		 
mPW1PW91 42.1 a
0.0 b 		12.5 a
0.0 b 		15.7 a
0.0 b 		2.2 a
0.0 b 		15.5 a
0.0 b 		15.4 a
0.0 b 		15.8 a
0.0 b 		19.7 a
0.0 b 		22.0 a
0.0 b 		21.3 a
0.0 b 		    17.9 a
0.0 b 		18.0 a
0.0 b 		  19.5 a
0.0 b 		NC  
0.0 b 		 
M06-2X     21.0 a
0.0 b 		 
0.0 b 		                             
PBEPBE
0.0 b 		23.2 a
0.0 b 		NC NC 23.0 a
0.0 b 		22.9 a
0.0 b 		23.8 a
0.0 b 		28.0 a
0.0 b 		27.3 a
0.0 b 		25.5 a
0.0 b
0.0 b 		  25.7 a
0.0 b 		25.7 a
0.0 b 		  NC NC  
0.0 b 		 
PBEPBEultrafine        
0.0 b 		                             
PBE1PBE         19.5 a
0.0 b 		                             
HSEh1PBE  
0.0 b 		   
0.0 b 		 
0.0 b 		           
0.0 b 		           
TPSSh         18.8 a
0.0 b 		  18.3 a
0.0 b 		    21.2 a
0.0 b 		      20.2 a
0.0 b 		           
wB97X-D     20.3 a
0.0 b 		    a     a   25.8 a
0.0 b 		      a   a   a       a      
B97D3   18.8 a
0.0 b 		    18.6 a
0.0 b 		  18.5 a
0.0 b 		  22.9 a
0.0 b 		  20.8 a
0.0 b 		19.6 a
0.0 b 		  20.4 a
0.0 b 		    20.1 a
0.0 b 		     
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ
Moller Plesset perturbation MP2 NC   a   a   a 61.6 a
0.0 b 		  a   a 65.4 a
0.0 b 		  a   a     a   a          
0.0 b 		 
MP2=FULL   a   a   a   a   a   a   a   a   a NC       a          
0.0 b 		 
ROMP2 NC NC NC NC NC NC NC NC NC NC     NC NC   NC        
MP3         34.7 a
0.0 b 		 
0.0 b 		                         
MP3=FULL         34.5 a
0.0 b 		  32.9 a
0.0 b 		                         
MP4     a
0.0 b
0.0 b 		  a    
0.0 b 		NC         NC            
B2PLYP        
0.0 b 		 
0.0 b 		            30.1 a
0.0 b 		           
B2PLYP=FULL  
0.0 b 		   
0.0 b 		 
0.0 b 		                         
Configuration interaction CID   23.4 a
0.0 b 		23.5 a
0.0 b 		11.1 a
0.0 b 		26.8 a
0.0 b
0.0 b
0.0 b 		30.7 a
0.0 b 		       
0.0 b
0.0 b 		       
0.0 b 		 
CISD   16.9 a
0.0 b 		16.9 a
0.0 b 		3.8 a
0.0 b 		23.2 a
0.0 b
0.0 b
0.0 b 		28.1 a
0.0 b 		       
0.0 b
0.0 b 		       
0.0 b 		 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ
Quadratic configuration interaction QCISD   19.8 a
0.0 b 		19.8 a
0.0 b 		7.3 a
0.0 b 		23.2 a
0.0 b 		22.6 a
0.0 b 		22.2 a
0.0 b 		29.2 a
0.0 b 		NC       27.0 a
0.0 b 		    NC        
QCISD(T)  
0.0 b
0.0 b
0.0 b 		24.4 a
0.0 b
0.0 b
0.0 b 		          29.7 a
0.0 b 		             
Coupled Cluster CCD   34.5 a
0.0 b 		34.5 a
0.0 b 		22.1 a
0.0 b 		35.9 a
0.0 b 		35.3 a
0.0 b 		34.5 a
0.0 b 		40.1 a
0.0 b 		NC       38.8 a
0.0 b 		    NC        
CCSD  
0.0 b 		    19.9 a
0.0 b
0.0 b
0.0 b 		          24.6 a
0.0 b 		             
CCSD(T)           a                 a          
0.0 b 		 
CCSD(T)=FULL         NC                              
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-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 -44.6 a
0.0 b 		-8.1 a
0.0 b 		-46.2 a
0.0 b 		  a   a   a     -6.2 a
0.0 b
density functional B1B95
0.0 b 		               
B3LYP 6.5 a
0.0 b 		21.0 a
0.0 b 		2.0 a
0.0 b 		18.4 a
0.0 b 		3.5 a
0.0 b 		3.7 a
0.0 b 		    21.5 a
0.0 b
PBEPBE                 25.8 a
0.0 b
Moller Plesset perturbation MP2   a   a   a   a   a   a     61.1 a
0.0 b
Single point energy calculations (select basis sets)
cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// HF/6-31G*  
0.0 b
MP2FC// B3LYP/6-31G*  
0.0 b
MP4// HF/6-31G*  
0.0 b
MP4// B3LYP/6-31G*  
0.0 b
MP4// MP2/6-31G*  
0.0 b
Coupled Cluster CCSD(T)// HF/6-31G*  
0.0 b
CCSD(T)// B3LYP/6-31G*  
0.0 b
CCSD(T)//B3LYP/6-31G(2df,p)
0.0 b
0.0 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.