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
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XII	Geometries
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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 MgCl (magnesium monochloride)

Experimental Ionization Energy is 7.49 ± 0.1 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.

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	G4	7.763
composite	CBS-Q	7.642

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	3.488	7.902	7.630	7.962	7.642	7.642	7.662	7.672	7.672	7.572		7.547	7.638	7.572	7.559		7.575	7.560	7.566	7.572
density functional	LSDA	4.501	4.164	8.260	8.563	8.283	8.283	8.325	8.364	8.364	8.236			8.291	8.258		8.336
	BLYP	3.955	7.923	7.717	7.983	7.732	7.732	7.788	7.820	7.820	7.693
	B1B95	3.780		7.684	8.022	7.732	7.722				7.663			7.727	7.676
	B3LYP	4.157	8.138	7.910	8.200	7.927	7.926	7.970	7.999	7.999	7.877		7.941	7.928		7.890		7.906	7.894	7.889
	B3LYPultrafine					7.926												7.906
	B3PW91	4.122	8.132	7.888	8.195	7.896	7.896	7.925	7.948	7.948	7.842
	mPW1PW91	4.088	8.099	7.882	8.189	7.853	7.853	7.882	7.901	7.931	7.827				7.827
	M06-2X			7.757		7.927						7.883
	PBEPBE	3.963	8.049	7.828	8.089	7.814	7.814	7.856	7.882	7.882	7.769			7.825	7.774
	PBE1PBE					7.871
	HSEh1PBE		8.119			7.867		7.898							7.814
	TPSSh					7.756		7.783			7.701				7.702
	wB97X-D			7.564		7.653		7.685		7.699			7.644	7.685	7.592			7.600
	B97D3		7.660			7.450		7.487		7.505		7.400	7.495		7.406			7.419			7.418
		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	3.309	7.758	7.547	7.821	7.565	7.565	7.598	7.607	7.607	7.584		7.494	7.586	7.587	7.596	7.680	7.614	7.607
	MP2=FULL		7.759			7.574	7.574	7.607	7.623	7.623						7.628				7.602
	MP3					7.588
	MP3=FULL					7.598		7.630
	MP4					7.563
	B2PLYP					7.740									7.727
	B2PLYP=FULLultrafine					7.743								7.751	7.733			7.752
Configuration interaction	CID					7.597			7.635
Configuration interaction	CISD					7.593
		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		7.765			7.585	7.585	7.617	7.627	7.627				7.604	7.610
Quadratic configuration interaction	QCISD(T)					7.573
Coupled Cluster	CCD					7.593			7.634					7.611
	CCSD					7.590
	CCSD(T)													7.594	7.605		7.694	7.637
		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	8.027	7.697	8.075	7.716	7.965	7.923			7.572
density functional	B3LYP	8.128	7.831	8.150	7.837	8.069	8.172			7.909
density functional	PBEPBE									7.797
Moller Plesset perturbation	MP2	7.898	7.668	7.932	7.673	7.842	7.771			7.594

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.