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
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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 BeCl (beryllium monochloride)

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.

Original data displayed. Press to display differences.

Differences displayed. Press to display original data.

Ionization Energies in eV

Methods with predefined basis sets
semi-empirical	PM3
composite	G2	8.660
	G3	8.763
	G4	8.759
	CBS-Q	8.697

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	7.928	8.935	8.738	8.915	8.626	8.626	8.661	8.647	8.647	8.562		8.655	8.643	8.600	8.588		8.605	8.588	8.589	8.603
density functional	LSDA	8.378	5.918	9.166	9.281	9.066	9.066	9.127	9.115	9.115	9.022			9.101	9.079		9.151
	BLYP	7.932	8.818	8.683	8.797	8.597	8.597	8.675	8.656	8.656	8.563			8.635
	B1B95	8.046		8.734	8.865	8.635	8.617	8.667	8.652	8.652	8.565			8.656			8.715
	B3LYP	8.168	9.046	8.893	9.026	8.798	8.798	8.860	8.842	8.842	8.755		8.853	8.830	8.799	8.791		8.808	8.793	8.788
	B3LYPultrafine					8.798												8.808
	B3PW91	8.227	9.086	8.931	9.067	8.818	8.818	8.860	8.837	8.837	8.765			8.844	8.798
	mPW1PW91	8.230	9.065	8.932	9.074	8.790	8.790	8.836	8.811	8.836	8.761				8.795
	M06-2X			8.798		8.693						8.695
	PBEPBE	8.068	8.959	8.822	8.937	8.717	8.717	8.780	8.754	8.754	8.670			8.754	8.710
	PBE1PBE					8.792
	HSEh1PBE		9.060			8.786		8.833							8.767
	TPSSh					8.739		8.781			8.687				8.717
	wB97X-D			8.706		8.574		8.620		8.602			8.664	8.620	8.562			8.569
	B97D3		8.620			8.383		8.436		8.406		8.372	8.464		8.375			8.392			8.391
		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	7.596	8.735	8.618	8.713	8.509	8.509	8.558	8.572	8.572	8.564		8.567	8.590	8.619		8.687	8.645
	MP2=FULL	7.594	8.736			8.504	8.504	8.553	8.573	8.573										8.599
	MP3					8.540
	MP3=FULL					8.536		8.584
	MP4					8.500
	B2PLYP					8.631									8.671
	B2PLYP=FULLultrafine					8.630								8.682	8.667			8.683
Configuration interaction	CID					8.554			8.612
Configuration interaction	CISD					8.545
		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		8.754			8.534	8.534	8.583	8.602	8.602				8.618	8.654
Quadratic configuration interaction	QCISD(T)					8.515
Coupled Cluster	CCD					8.550			8.612					8.628
	CCSD					8.542
	CCSD(T)													8.605	8.648		8.709	8.679
	CCSD(T)=FULL					8.514								8.604	8.635		8.706	8.666
		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

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	9.073	8.726	9.034	8.700	9.044	8.579			8.603
density functional	B3LYP	9.154	8.850	9.101	8.821	9.164	8.656			8.805
density functional	PBEPBE									8.725
Moller Plesset perturbation	MP2	8.892	8.689	8.840	8.657	8.826	8.299			8.639

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.