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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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 C₃H₃N (acrylonitrile)

Experimental Ionization Energy is 10.91 ± 0.01 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	G4	10.897
	CBS-Q	10.826

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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	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
hartree fock	HF	7.424	9.343	9.343	9.211	9.211	9.209	9.311	9.304	9.309	9.172		9.348	9.243	9.307	9.272	9.317	9.317
density functional	BLYP	8.687	10.103	10.103	10.089	10.036	10.043	10.259	10.258	10.269	10.051			10.124	10.299
	B1B95	9.116	10.534	10.534	10.506	10.353	10.557	10.577	10.580	10.587	10.427			10.488	10.508	10.490	10.527
	B3LYP	8.978	10.407	10.407	10.375	10.321	10.326	10.503	10.511	10.521	10.325		10.569		10.541	10.517	10.563
	B3LYPultrafine					10.321									10.541		10.564
	B3PW91	9.071	10.522	10.522	10.448	10.395	10.400	10.530	10.546	10.555	10.388			10.452	10.556
	mPW1PW91	9.052	10.472	10.511	10.432	10.340	10.344	10.478	10.484	10.529	10.366			10.396	10.495	10.506
	M06-2X			10.678		10.559					10.571	10.758			10.753		10.767
	PBEPBE	8.897	10.346	10.346	10.301	10.247	10.252	10.429	10.424	10.434	10.250			10.321	10.456	10.438	10.485
	PBEPBEultrafine					10.247
	PBE1PBE					10.362
	HSEh1PBE		10.472			10.344									10.509
	TPSSh					10.223		10.363			10.211				10.386
	wB97X-D			10.548		10.413		10.550		10.574			10.590	10.550	10.554		10.568
	B97D3		10.272			10.154		10.324		10.328		10.373	10.377		10.338		10.366	10.367
		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	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
Moller Plesset perturbation	MP2	9.681	10.946	10.946	11.095	11.019	11.067	11.231	11.180	11.241	11.229		11.256	11.188	11.429	11.379	11.499
	MP2=FULL		10.948			11.022	11.071	11.234	11.187	11.248	11.228			11.192	11.436		11.502
	MP3					10.572
	MP3=FULL					10.577		10.765
	B2PLYP					10.386					10.457				10.662		10.699
	B2PLYP=FULLultrafine					10.389								10.484	10.669		10.706
Configuration interaction	CID					10.240
	CISD					10.176
		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	aug-cc-pVDZ	aug-cc-pVTZ	daug-cc-pVTZ
Quadratic configuration interaction	QCISD		10.261			10.299	10.342	10.477	10.457	10.510	10.494				10.673		10.724
Coupled Cluster	CCD					10.631
	CCSD					10.322									10.696
	CCSD=FULL														10.721
	CCSD(T)					10.391
		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	aug-cc-pVDZ	aug-cc-pVTZ	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	9.155	9.129	9.225	9.275	9.278	9.281			9.322
density functional	B3LYP	10.323	10.223	10.397	10.349	10.492	10.484			10.559
	PBEPBE									10.476
Moller Plesset perturbation	MP2	11.180	11.030	11.286	11.129	11.320	11.326			11.456

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.