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

---

NIST policy on privacy, security, and accessibility.

---

© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

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

Calculated Ionization Energy for Se (Selenium atom)

Experimental Ionization Energy is 9.75238 eV

---

Ionization Energies in eV

Methods with predefined basis sets

semi-empirical	PM3
	PM6
composite	G1	9.538
	G2MP2	9.425
	G2	9.522
	G3	9.710
	G3B3	11.536
	G3MP2	11.519
	G4	11.526
	CBS-Q	9.621

---

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-pVDZ	daug-cc-pVTZ
hartree fock	HF	6.191	8.214	8.412	8.461	8.521	8.521	8.561	8.537	8.537	8.578	8.587	8.525	8.551	8.578	8.586	8.577	8.587	8.587	8.570	8.587
	ROHF		8.213	8.334	8.462	8.443	8.443	8.482	8.457	8.457		8.479	8.446	8.474	8.471	8.474	8.494	8.475	8.475	8.486	8.475
density functional	LSDA	8.164	4.048	10.182	10.281	10.292	10.322	10.344	10.374	10.372	10.297			10.337	10.419		10.419
	BLYP	7.437	9.275	9.454	9.512	11.549	9.558	9.650	9.675	9.675	9.586	9.712	9.660	9.522	9.689		9.686	9.697		9.684	9.696
	B1B95	7.559	9.437	9.437	9.534	9.552	9.552	9.608	9.604	9.604	9.583	9.634	9.591	9.594	9.618		9.633	9.622		9.628	9.622
	B3LYP	7.645	9.469	9.637	9.709	9.737	9.737	9.808	9.821	9.821	9.766	9.854	9.808	9.781	9.837	9.842	9.837	9.842	9.843	9.834	9.841
	B3LYPultrafine		9.469			9.737	9.737	9.808	9.820		9.766	9.854	9.808	9.781	9.837		9.838	11.824		9.834	9.841
	B3PW91	7.666	9.417	9.580	9.645	9.669	9.669	9.717	9.717	9.717	9.699	9.751	9.708	9.711	9.739		9.742	9.743		9.737	9.742
	mPW1PW91	7.627	9.368	9.531	9.592	9.619	9.619	9.669	9.665	9.665	9.649	9.704	9.660	9.659	9.693		9.692	9.699		9.687	9.698
	M06-2X	7.465	9.415	9.520	9.517	9.561	9.561	9.615	9.594	9.594	9.575	9.627	9.578	9.576	9.571		9.612	9.576		9.607	9.576
	PBEPBE	7.550	9.299	9.462	9.523	9.554	9.554	9.626	9.645	9.645	9.581	9.686	9.633	9.600	9.664		9.657	9.673		9.653	9.672
	PBEPBEultrafine		9.299			9.554	9.554	9.626	9.642		9.581	9.686	9.633	9.601	9.663		9.657	9.672		9.653	9.672
	PBE1PBE	7.581	9.491	9.491	9.551	9.577	9.577	9.628	9.630	9.630	9.607	9.669	9.624	9.618	9.656		9.652	9.662		9.647	9.662
	HSEh1PBE	7.573	9.374	9.541	9.591	9.614	9.614	9.666	9.673	9.673	9.646	9.712	9.671	9.658	9.704		9.693	9.709		9.688	9.708
	TPSSh	7.552	9.324	9.496	9.551	10.515	9.584	10.564	9.638	9.638	9.609	9.677	9.638	9.631	10.529	9.673	9.660	9.673	9.675	9.655	9.673
	wB97X-D	7.588	9.567	9.712	9.747	9.739	9.739	9.788	9.788	9.788	9.772	9.819	9.800	9.805	9.823	9.828	9.835	9.825	9.829	9.830	9.825
	B97D3	7.418	9.159	9.187	9.395	9.379	9.360	9.386	9.435	9.484	9.478	9.443	9.418	9.442	9.460	9.334	9.529	9.441	9.609	9.515	9.346
		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-pVDZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2	6.190	8.388	8.857	8.650	11.649	8.955	9.000	11.668	8.986	9.197	9.250	9.003	8.976	9.292	9.426	9.090	9.334	9.446	9.085	9.334
	MP2=FULL	6.189	8.388	8.858	8.648	8.980	8.980	9.025	9.035	9.035	9.233	9.307	8.991	8.978	9.288	9.417	9.091	11.847	9.437	9.086	9.330
	ROMP2	6.190	8.879	8.879	8.650	8.985	8.985	9.028	9.020	9.020	9.236	9.292	9.027	8.998	9.326		9.114			9.109	9.369
	MP3					8.973		12.080				9.338	8.990	8.974	9.353					9.102	9.397
	MP3=FULL		8.419	8.856	8.682	11.607	8.984	11.659	9.013	9.013	9.295	9.352	8.975	8.972	9.342		9.105	9.386		9.099	9.387
	MP4		8.427			8.974				9.016		9.378	9.012	8.976	9.404		9.122	9.453		9.118	9.453
	MP4=FULL		8.426			8.988				9.049		9.420		8.976	9.400		9.123	9.449		9.118	9.449
	B2PLYP	7.131	9.076	9.342	9.319	9.439	9.439	9.498	9.498	9.498	9.540	9.607	9.496	9.472	11.753		9.549	9.630		9.545	9.630
	B2PLYP=FULL	7.131	11.280	9.343	9.318	11.690	9.448	11.753	9.515	9.515	9.553	9.628	9.493	9.473	9.611		9.549	9.629		9.545	9.629
	B2PLYP=FULLultrafine	7.131	9.076	9.343	9.318	9.448	9.448	9.507	9.515	9.515	9.553	9.628	9.493	9.473	9.611		9.549	9.629		9.545	9.629
Configuration interaction	CID		8.427	8.813	8.693	8.928			8.960			9.285		8.929	9.284					9.046	9.321
	CISD		8.426	8.826	8.693	8.942			8.974			9.301		8.942	9.300					9.061	9.338
		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-pVDZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		8.430	8.867	8.697	8.980	8.980	9.027	9.017	9.017	9.310	9.365	9.010	8.981	9.389		9.118	9.432		9.113	9.433
	QCISD(T)					8.986			9.030			9.394	9.024	8.988	9.418		9.137	9.468		9.133	9.469
	QCISD(T)=FULL					9.000		9.048				9.427		8.987	9.411	9.561	9.137	9.462	9.579	9.132	9.463
Coupled Cluster	CCD		8.430	8.852	8.697	8.965	8.965	9.013	9.002	9.002	9.292	9.346	8.993	8.967	9.367		9.100	9.410		9.095	9.411
	CCSD					8.979	8.979	9.026	9.016	9.016	9.309	9.363	9.009	8.981	9.387	9.528	9.117	9.430	9.544	9.112	9.430
	CCSD=FULL					8.991					9.327	9.391	8.996	8.979	9.378	9.515	9.115	9.421	9.531	9.110	9.421
	CCSD(T)					8.986	8.986	9.035	9.030	9.030	9.335	9.393	9.024	8.987	9.417	9.570	9.137	9.467	9.587	9.132	9.468
	CCSD(T)=FULL					8.999						9.425	9.012	8.987	9.410	9.559	9.136	9.460	9.577	9.131	9.461
		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-pVDZ	daug-cc-pVTZ

---

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	8.402		8.402		8.504	8.466	8.549		8.587
	ROHF							8.444		8.479
density functional	LSDA							10.298
	BLYP							9.633		9.692
	B1B95							9.566		9.624
	B3LYP	9.741		9.741		9.807	9.798	9.789		9.842
	B3LYPultrafine							9.789		9.842
	B3PW91							9.685		9.747
	mPW1PW91							9.638		9.701
	M06-2X							9.511		9.610
	PBEPBE							9.601		9.671
	PBEPBEultrafine							9.601		9.671
	PBE1PBE							9.602		9.665
	HSEh1PBE							9.652		9.711
	TPSSh							9.615		9.677
	wB97X-D	9.705		9.705		9.805	9.752	9.777		9.834
	B97D3							9.445		9.606
Moller Plesset perturbation	MP2	8.546		8.546		8.633	8.609	9.276		9.304
	MP2=FULL							9.274		9.293
	ROMP2							9.308		9.339
	MP3							9.337		9.361
	MP3=FULL							9.329		9.346
	MP4							9.389		9.416
	MP4=FULL							9.385		9.407
	B2PLYP							9.577		9.620
	B2PLYP=FULL							9.577		9.617
	B2PLYP=FULLultrafine							9.577		9.617
Configuration interaction	CID							9.268		9.278
	CISD							9.284		9.294
Quadratic configuration interaction	QCISD							9.371		9.399
	QCISD(T)							9.401		9.429
	QCISD(T)=FULL							9.396		9.417
Coupled Cluster	CCD							9.351		9.377
	CCSD							9.369		9.397
	CCSD=FULL							9.362		9.383
	CCSD(T)							9.400		9.427
	CCSD(T)=FULL							9.395		9.416

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.