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Comparison of experiment and theory for aICI

18 10 24 13 42
Species with coordinate aICI
Species Name
CH2I2 Diiodomethane
The small subscript is the number of angles with completed calculations.
Click on an entry for a histogram of the difference distribution.
rms differences (calculated - experiment) in degrees
Methods with predefined basis sets

rms differences (calculated - experiment) in degrees
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-311G* 6-311G**
hartree fock HF 4.11 2.41 1.11 2.11 2.11
density functional LSDA       2.11 2.11
BLYP 4.81 3.11 1.81 3.11 3.11
B1B95 4.61 0.81 0.81 2.11 2.01
B3LYP 4.51 2.71 1.51 2.71 2.61
B3LYPultrafine   2.71   2.71 2.61
B3PW91 4.61 2.61 1.21 2.41 2.41
mPW1PW91 4.51 2.51 1.01 2.31 2.21
M06-2X 4.01 1.71 0.41 1.71 1.61
PBEPBE 4.81 2.81 1.31 2.61 2.61
PBEPBEultrafine   2.81   2.61 2.61
PBE1PBE 4.41 0.91 0.91 2.21 2.11
HSEh1PBE 4.41 2.51 1.01 2.31 2.21
TPSSh 4.71 2.71 1.21 2.31 2.31
wB97X-D 4.31 2.31 0.91 2.21 2.21
B97D3 4.61 2.71 1.51 2.71 2.71
STO-3G 3-21G 3-21G* 6-311G* 6-311G**
Moller Plesset perturbation MP2 3.91 2.41 0.11 1.81 2.01
MP2=FULL 3.91 2.41 0.01 1.81 2.01
MP3       2.01 2.11
MP3=FULL   2.51 0.31 2.01 2.21
MP4   2.31   1.81 1.91
MP4=FULL   2.31   1.81 2.01
B2PLYP 4.21 2.51 0.81 2.21 2.31
B2PLYP=FULL 4.21 2.51 0.81 2.21 2.31
B2PLYP=FULLultrafine 4.21 2.51 0.81 2.21 2.31
Configuration interaction CID   2.51 0.51 2.01 2.21
CISD   2.41 0.51 2.01 2.11
STO-3G 3-21G 3-21G* 6-311G* 6-311G**
Quadratic configuration interaction QCISD   2.31 0.31 1.91 2.11
QCISD(T)       1.71 2.01
QCISD(T)=FULL       1.81 2.01
Coupled Cluster CCD   2.41 0.31 2.01 2.11
CCSD       1.91 2.11
CCSD=FULL       1.91 2.11
CCSD(T)       1.81 2.01
CCSD(T)=FULL       1.81 2.01
STO-3G 3-21G 3-21G* 6-311G* 6-311G**

rms differences (calculated - experiment) in degrees
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 2.31   2.21   2.01 1.81 1.61   1.51
density functional LSDA             1.31    
BLYP             2.51   2.51
B1B95             1.41   1.31
B3LYP 2.51   2.61   2.31 2.11 2.11   2.01
B3LYPultrafine             2.11   2.01
B3PW91             1.71   1.71
mPW1PW91             1.61   1.51
M06-2X             1.01   1.01
PBEPBE             1.91   1.91
PBEPBEultrafine             1.91   1.91
PBE1PBE             1.51   1.51
HSEh1PBE             1.61   1.51
TPSSh             1.71   1.61
wB97X-D 2.11   2.21   1.81 1.71 1.51   1.51
B97D3             2.11   2.11
Moller Plesset perturbation MP2 2.41   2.41   2.11 1.91 1.01   0.71
MP2=FULL             1.01   0.71
MP3             1.41   1.41
MP3=FULL             1.41   1.51
MP4             1.11   0.81
MP4=FULL             1.21   0.81
B2PLYP             1.61   1.51
B2PLYP=FULL             1.61   1.51
B2PLYP=FULLultrafine             1.61   1.51
Configuration interaction CID             1.51   1.51
CISD             1.51   1.51
Quadratic configuration interaction QCISD             1.31   1.11
QCISD(T)             1.21   1.11
QCISD(T)=FULL             1.31   1.11
Coupled Cluster CCD             1.31   1.21
CCSD             1.31   1.21
CCSD=FULL             1.31   1.21
CCSD(T)             1.21   1.11
CCSD(T)=FULL             1.31   1.11
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.