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 LiO (lithium oxide)

Experimental Ionization Energy is 8.44 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

semi-empirical	PM3
composite	G2	8.115
	G3	8.118
	G3B3	8.426
	G4	8.469
	CBS-Q	8.190

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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	cc-pV(T+d)Z	daug-cc-pVTZ
hartree fock	HF	3.592	5.602	5.602	5.917	6.019	6.019	6.215	6.141	6.479	6.142		6.449	6.381	6.590	6.629	6.611	6.632	6.639	6.590	6.631
	ROHF		5.964	5.964	6.320	6.456	6.456	6.655	6.543	6.543				6.438	6.652	6.689	6.666	6.691	6.698
density functional	LSDA	7.909	8.956	8.956	9.241	9.364	9.364	9.631	9.517	9.517	9.487			9.352	9.658		9.642	9.719		9.658
	BLYP	6.583	8.153	8.153	8.406	8.510	8.510	8.436	8.360	8.630	8.625			8.505	8.781
	B1B95	-3.768	-2.160		8.019						8.252			-2.000	8.377
	B3LYP	6.334	7.809	7.809	8.030	8.145	8.145	8.385	8.310	8.596	8.302		8.597	8.467	8.741	8.796	8.729	8.802	8.814	8.741
	B3LYPultrafine					8.476												8.802
	B3PW91	6.107	7.636	7.636	7.857	7.975	7.975	8.191	8.129	8.438	8.118			8.308	8.560
	mPW1PW91	5.988	7.556	7.868	8.129	7.877	7.877	8.094	8.033	8.362	8.351			8.236	8.483					8.483
	M06-2X			7.924		8.266						8.588
	PBEPBE	6.533	8.153	8.153	8.392	8.495	8.495	8.739	8.609	8.609	8.603			8.490	8.751					8.751
	PBE1PBE					8.230
	HSEh1PBE		7.851			8.237		8.469							8.478
	TPSSh					8.195		8.416			8.291				8.429
	wB97X-D			7.759		8.201		8.441		8.293			8.252	8.441	8.411			8.460
	B97D3		7.922			8.251		8.481		8.357		8.553	8.314		8.475			8.535			8.534
		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	4.268	6.754	6.754	7.153	7.490	7.487	7.753	7.613	7.886	7.861		7.876	7.742	8.291	8.464	8.201	8.425		8.291
	MP2=FULL	4.269	6.760	7.014	7.473	7.838	7.510	7.834	7.641	7.911	8.177			7.750	8.334	8.522		8.496
	ROMP2	4.658	8.517	8.517	8.932	10.648	10.648	10.954	11.171	11.171	11.901			10.727	12.399		11.376
	MP3					7.672
	MP3=FULL					7.686		7.993
	MP4		7.040			7.414				7.822					8.237
	B2PLYP					8.175									8.504
	B2PLYP=FULLultrafine					8.180								8.151	8.517			8.610
Configuration interaction	CID		6.853	6.853	7.311	7.572			7.620
	CISD		6.923	6.923	7.355	7.596			7.651
		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		6.748	7.011	7.452	7.371	7.712	7.631	7.485	7.768	8.035			7.642	8.135					8.135
	QCISD(T)					7.398								7.670	8.217		8.129	8.358
Coupled Cluster	CCD		6.905	6.905	7.378	7.662	7.662	7.927	7.426	7.712	7.994			7.582	8.093		8.020	8.216
	CCSD					7.346
	CCSD(T)													7.663	8.210	8.385	8.120	8.350		8.210
	CCSD(T)=FULL					7.742										8.452
		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

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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	6.122	6.228	6.512	6.596	6.015	6.025			6.597
density functional	B3LYP	8.050	8.134	8.349	8.436	8.422	8.417			8.746
	PBEPBE									8.752
Moller Plesset perturbation	MP2	7.362	7.679	7.757	8.046	7.307	7.324			8.274

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.