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
VII	Tutorials and Units
VIII	Links to other sites
IX	Feedback
X	Older CCCBDB versions
XII	Geometries
XIII	Vibrations
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 O₃ (Ozone)

Experimental Ionization Energy is 12.53 ± 0.08 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	12.600
	G3	12.531
	G3B3	12.562
	G4	12.544
	CBS-Q	12.629

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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	aug-cc-pVQZ	daug-cc-pVTZ
hartree fock	HF	9.968				12.565	12.565	12.644	12.565	12.565	12.382		12.572	12.477	12.395	12.406	12.581	12.452	12.426	12.438
density functional	LSDA	9.353	12.608	12.608	13.024	12.683	12.684	12.959	12.818	12.818	12.566			12.574	12.762		12.903	12.871
	BLYP	8.729	11.782	11.782	12.248	11.943	11.943	12.279	12.075	12.075	11.812			11.837	12.053
	B1B95	9.325	12.257	12.257	12.455	12.105	12.105	12.296	12.158	12.158	11.975			12.012	12.086		12.250	12.178
	B3LYP	9.481	12.586	12.586	12.845	12.475	12.475	12.731	12.568	12.568	12.336		12.664	12.372	12.512	12.560	12.674	12.623	12.606
	B3LYPultrafine					12.475												12.622
	B3PW91	9.528			12.845	12.447	12.447	12.634	12.516	12.516	12.308			12.364	12.422
	mPW1PW91	9.585	12.674	12.674	12.884	12.472	12.472	12.661	12.531	12.531	12.330			12.391	12.435
	M06-2X			13.088		12.832						12.943
	PBEPBE	8.806	11.953	11.953	12.328	11.971	11.971	12.253	12.072	12.072	11.846			11.886	12.035
	PBE1PBE					12.408
	HSEh1PBE		12.593			12.406		12.603							12.389
	TPSSh					12.217		12.414							12.250
	wB97X-D			12.774		12.587		12.758		12.632			12.620	12.758	12.481			12.557
	B97D3		12.126			12.045		12.285		12.134		12.197	12.209		12.063			12.176		12.167
		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	daug-cc-pVTZ
Moller Plesset perturbation	MP2		11.088	11.088	11.564	11.588	11.588	11.832	11.534	11.534	11.673		11.673	11.393	11.807		11.889
	MP2=FULL		11.088	11.088	11.564	11.587	11.587	11.832	11.539	11.539	11.673			11.394	11.806
	MP3					12.690
	MP3=FULL					12.689		12.844
	B2PLYP					11.965									12.070
	B2PLYP=FULLultrafine					11.966								11.850	12.071			12.214
Configuration interaction	CID				12.755	12.489			12.479
	CISD		12.334	12.334	12.678	12.430			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	aug-cc-pVQZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD								12.248	12.248	12.344				12.451
	QCISD(T)					12.048								11.892	12.247		12.335
Coupled Cluster	CCD				12.674	12.467	12.467	12.646	12.456	12.456	12.533			12.307	12.638		12.682
	CCSD					12.367
	CCSD(T)													11.960	12.311		12.393
		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	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		12.637		12.579					12.428
density functional	B3LYP		12.574		12.593	12.872	12.856			12.578
	PBEPBE									12.107
Moller Plesset perturbation	MP2	11.617	11.718		11.752	11.550				11.880

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.