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 NO (Nitric oxide)

Experimental Ionization Energy is 9.2642 ± 0.00002 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	9.321
	G3	9.401
	G3B3	9.305
	G3MP2	9.389
	G4	9.267
	CBS-Q	9.370

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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	9.565	9.991	9.991	10.237	9.243	9.243	9.269	9.087	9.087	9.016	9.015	9.066	9.075	9.001	8.984	9.152	9.016	8.992	9.001	9.008
density functional	LSDA	9.294	10.340	10.340	10.634	10.075	10.075	10.218	10.021	10.021	9.925	10.036	10.047	9.919	9.983		10.128	10.030		9.983
	BLYP	8.849	9.785	9.785	10.083	9.529	9.529	9.716	9.478	9.478	9.384	9.540	9.553	9.374	9.464		9.633	9.537		9.464
	B1B95	9.061	9.864	9.864	10.081	9.439	9.439	9.632	9.338	9.435	9.278	9.441	9.465	9.290	9.293	9.296	9.441	9.332	9.315
	B3LYP	9.254	10.121	10.121	10.418	9.782	9.782	9.918	9.703	9.703	9.617	9.721	9.746	9.626	9.666	9.680	9.826	9.717	9.703	9.666
	B3LYPultrafine		10.121			9.782	9.782	9.917	9.703		9.617	9.720	9.746	9.626	9.666		9.826	9.717
	B3PW91	9.274	10.199	10.199	10.397	9.753	9.753	9.842	9.662	9.662	9.592	9.650	9.672	9.610	9.609		9.752	9.644		9.609
	mPW1PW91	9.298	10.206	10.206	10.399	9.737	9.737	9.829	9.641	9.641	9.575	9.635	9.664	9.595	9.593		9.740	9.633		9.593
	M06-2X	9.137	10.103	10.103	10.315	9.560	9.560	9.651	9.507	9.507	9.394	9.488	9.486	9.400	9.464		9.548	9.493
	PBEPBE	8.880	9.888	9.888	10.110	9.537	9.537	9.688	9.476	9.476	9.404	9.526	9.538	9.397	9.465	9.487	9.611	9.530	9.519	9.465
	PBEPBEultrafine		9.888			9.537	9.537	9.688	9.476		9.404	9.526	9.538	9.397	9.465		9.611	9.530
	PBE1PBE	9.192	10.131	10.131	10.338	9.675	9.675	9.771	9.582	9.582	9.520	9.584	9.611	9.534	9.545		9.684	9.587
	HSEh1PBE	9.189	10.267	10.128	10.340	9.678	9.678	9.932	9.588	9.588	9.521	9.588	9.618	9.533	9.709		9.685	9.592
	TPSSh	9.121	10.137	10.137	10.290	9.664	9.664	9.760	9.581	9.581	9.502	9.580	9.615	9.527	9.543	9.555	9.673	9.586	9.579
	wB97X-D	9.226	10.144	10.144	10.324	9.672	9.672	9.748	9.559	9.559	9.485	9.521	9.547	9.950	9.460	9.472	9.642	9.489	9.492
	B97D3	9.020	10.015	10.015	10.155	9.560	9.560	9.684	9.491	9.491	9.408	9.511	9.542	9.421	9.461	9.480	9.598	9.517	9.510		9.513
		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	6.293	8.027	8.027	8.259	8.496	8.496	8.598	8.451	8.451	8.609	8.761	8.465	8.366	8.684	8.775	8.642	8.776	8.816	8.683
	MP2=FULL	5.119	8.024	8.024	8.257	8.497	8.497	8.599	8.456	8.456	8.609	8.774	8.471	8.366	8.687	8.792	8.642	8.775	8.833
	MP3					9.048		9.242				9.197	8.948	8.874	9.144
	MP3=FULL		9.049	9.049	9.389	9.048	9.048	9.128	8.948	8.948	9.078	9.202	8.952	8.872	9.133		9.124	9.203
	MP4		4.974			8.585				8.507		8.856	8.523	8.453	8.893		8.754	8.877
	MP4=FULL		4.969			8.586				8.513		8.868		8.454	8.773		8.755	8.875
	B2PLYP	8.177	9.624	9.624	9.886	9.385	9.385	9.505	9.292	9.292	9.282	9.391	9.332	9.222	9.332		9.449	9.399
	B2PLYP=FULL	8.176	9.623	9.623	9.885	9.384	9.384	9.504	9.292	9.292	9.279	9.391	9.332	9.221	9.328		9.448	9.391
	B2PLYP=FULLultrafine	6.759	9.623	7.260	7.536	9.384	9.384	9.504	5.839	5.839	5.733	5.390	5.883	9.221	9.327		6.277	9.391
Configuration interaction	CID		8.965	8.965	9.266	8.991			8.892			9.107		8.829	9.061
	CISD		9.145	9.145	9.450	9.016			8.905			9.117		8.847	9.071
		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		9.289	9.289	9.563	9.069	9.069	9.163	8.943	8.943	9.083	9.193	8.962	8.878	9.136		9.154	9.226		9.136
	QCISD(T)					9.016			8.883			9.169	8.911	8.822	9.102		9.125	9.207
	QCISD(T)=FULL					9.014		9.115				9.169		8.819	9.084	9.190	9.122	9.175	9.233
	QCISD(TQ)					9.052		9.152				9.199		8.852	9.135	9.218	9.155	9.240	9.262
	QCISD(TQ)=FULL					9.049		9.149				9.197		8.850	9.115	9.218	9.151	9.203	9.261
Coupled Cluster	CCD		8.808	8.808	9.107	8.913	8.913	8.999	8.830	8.830	8.981	9.101	8.837	8.755	9.043		9.010	9.126
	CCSD					9.068					9.077	9.186	8.956	8.875	9.130	9.201	9.148	9.218	9.238
	CCSD=FULL					9.065					9.067	9.188	8.959	8.873	9.113	9.205	9.144	9.187	9.241
	CCSD(T)		9.108			8.996	8.996	9.097	8.860	8.860	9.030	9.147	8.887	8.801	9.079	9.165	9.103	9.183	9.209	9.079
	CCSD(T)=FULL					8.994						9.148	8.891	8.353		9.169			9.212
		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	10.693	9.463	10.530	9.256	10.403	10.399			8.995
density functional	LSDA									10.000
	BLYP									9.504
	B1B95									9.411
	B3LYP	10.900	10.099	10.755	9.966	10.611	10.591			9.690
	B3LYPultrafine									9.690
	B3PW91									9.620
	mPW1PW91									9.610
	M06-2X									9.419
	PBEPBE									9.495
	PBEPBEultrafine									9.495
	PBE1PBE									9.561
	HSEh1PBE									9.567
	TPSSh									9.556
	wB97X-D	10.702	9.902	10.552	9.751	10.419	10.403			9.487
	B97D3									9.487
Moller Plesset perturbation	MP2	8.146	8.482	8.137	8.476	8.082	8.074			8.703
	MP2=FULL									8.707
	MP3									9.150
	MP3=FULL									9.148
	MP4									8.794
	MP4=FULL									8.798
	B2PLYP									9.355
	B2PLYP=FULL									9.353
	B2PLYP=FULLultrafine									5.448
Configuration interaction	CID									9.066
	CISD									9.077
Quadratic configuration interaction	QCISD									9.149
	QCISD(T)									9.118
	QCISD(T)=FULL									9.115
	QCISD(TQ)									9.150
	QCISD(TQ)=FULL									9.146
Coupled Cluster	CCD									9.053
	CCSD									9.142
	CCSD=FULL									9.138
	CCSD(T)									9.095
	CCSD(T)=FULL									9.092

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.