National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
NIST Standard Reference Database 101

I	Introduction
II	Experimental data
III	Calculated data
IV	Data comparisons
V	Cost comparisons
VI	Input and output files
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IX	Feedback
X	Older CCCBDB versions
XII	Geometries
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XIV	Reaction data
XV	Entropy data
XVI	Bibliographic data
XVII	Ion data
XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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XVII.C.1. (III.D.6.)

Calculated Ionization Energy for BO₂ (Boron dioxide)

Experimental Ionization Energy is 14 ± 1 eV
Please note! These calculated ionizataion energies have the vibrational zero-point energy (zpe) included, but the zpe has NOT been scaled. Click on an entry for more details, including the ionization energy with a scaled zpe.

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Ionization Energies in eV

Methods with predefined basis sets

composite	G2	12.748
	G3	12.746
	G3MP2	12.798
	G4	12.991
	CBS-Q	12.716

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Ionization Energies in eV

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	daug-cc-pVTZ
hartree fock	HF	8.486	11.849	11.849	12.084	12.286	12.286	12.407	12.300	12.300	12.286		12.352	12.255	12.364	12.388	5.275	12.387	12.383
	ROHF		13.235	13.235		13.495	13.495	13.625	13.528					13.473	13.558
density functional	LSDA	10.216	13.001	13.001	13.352	13.304	13.304	13.544	13.481	13.481	13.295			13.314	13.512		13.527
	BLYP		12.050	12.050	12.402	12.356	12.356	12.277	12.533	12.533	12.340			12.378	12.587
	B1B95	9.712	12.477	12.477	12.792	12.655	12.771	12.968	12.874	12.874	12.749			12.773	12.787		12.822
	B3LYP	9.730	12.531	12.531	12.872	12.845	12.845	13.084	12.986	12.986	12.828		13.071	12.853	13.034		13.062	13.076
	B3LYPultrafine					12.845												13.076
	B3PW91		12.606	12.606	12.907	12.880	12.880	13.067	12.990	12.990	12.854			12.885	13.016
	mPW1PW91	9.804	12.601	12.635	12.926	12.874	12.874	13.064	12.977	13.007	12.879			12.880	13.005		13.074
	M06-2X			12.879								13.315
	PBEPBE		12.230	12.230	12.546	12.497	12.497	12.743	12.640	12.640	12.474			12.519	12.684		12.730	12.733
	PBE1PBE					12.860
	TPSSh					12.635		12.827			12.607				12.776
	wB97X-D			12.736		13.019		13.201		13.106			13.141	13.201	13.110			13.138
	B97D3		12.170			12.408		12.626		12.536		12.621	12.609		12.560			12.603	12.598
		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	daug-cc-pVTZ
Moller Plesset perturbation	MP2		12.529	12.529	13.067	13.253	13.253	13.471	13.329	13.329			13.433	13.221	13.681		13.573
	MP2=FULL	8.861	12.530			13.253	13.253	13.471	13.334	13.334				13.223			13.574
	MP3					13.005		13.005
	MP3=FULL					13.006		13.182
	MP4					12.777									13.153
	B2PLYP														12.943
	B2PLYP=FULL		12.322			12.707		12.929
	B2PLYP=FULLultrafine					12.707								12.708	12.948			13.011
Configuration interaction	CID					12.977
	CISD					12.756
		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	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		11.946			12.640	12.640		12.697					2.404
	QCISD(T)					12.406
Coupled Cluster	CCD													13.014
	CCSD					12.602
	CCSD(T)					12.419
		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	daug-cc-pVTZ

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Ionization Energies in eV

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	12.069	12.266	11.998	12.285	12.066	12.063			12.382
density functional	B3LYP	12.954	12.895	12.912	12.935	13.019	12.999			13.060
	PBEPBE									12.712
Moller Plesset perturbation	MP2	13.077	13.282	13.168	13.373	13.219	13.225			13.711

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.