National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

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III.F.2.

Completed calculations for C2H2+ (acetylene cation)

Methods and basis sets for which an energy has been calculated. "e" indicates just an energy has been calculated. "o" indicates an optimized geometry. "v" indicates vibrational frequencies. "s" followed by a number indicates completed calculations for different states (for example s1ov). "c" followed by a number indicates completed calculations for different conformations (for example c2ov).
See the Calculated Energies page (section III.A.1) for more calculated properties.
Methods with predefined basis sets
semi-empirical PM3 o
composite G1 e
G2MP2 e
G4 e

Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ aug-cc-pVTZ cc-pV(T+d)Z
hartree fock HF         ov           ov ov       ov
ROHF         ov                      
density functional BLYP         ov                     ov
B1B95                               ov
B3LYP                     ov ov       ov
B3LYPultrafine                             ov  
B3PW91                               ov
mPW1PW91                               ov
M06-2X     ov   ov                      
PBEPBE                       ov       ov
PBE1PBE         ov                      
HSEh1PBE   o     ov o               o    
TPSSh         ov ov     ov         ov    
wB97X-D     ov   ov ov   ov     ov   ov ov ov  
B97D3   ov     ov ov   ov   ov       ov ov  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ aug-cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2         ov   ov       ov ov       ov
MP2=FULL                             ov ov
MP3           ov                    
MP3=FULL         ov ov                    
MP4                           ov    
B2PLYP         ov                 ov    
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ aug-cc-pVTZ cc-pV(T+d)Z
Quadratic configuration interaction QCISD                               ov
QCISD(T)                               ov
Coupled Cluster CCD                               ov
CCSD(T)                               ov
CCSD(T)=FULL                               ov
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ aug-cc-pVTZ cc-pV(T+d)Z

Single point energy calculations (select basis sets)
cc-pVTZ aug-cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// B3LYP/6-31G* e    
MP2FC// MP2FC/6-31G*   e  
Coupled Cluster CCSD(T)// B3LYP/6-31G* e    
CCSD(T)//B3LYP/6-31G(2df,p) e   e
CCSD// MP2FC/6-31G*   e  
CCSD(T)// MP2FC/6-31G*   e  
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.