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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III.D.11.

Calculated Proton Affinity

Name	Species		Species	Name
Oxirene	C2H2O	→	CH3CHO+	acetaldehyde cation

Bonding changes
Bond type H-C changed by +2 Bond type C-O lost 2 Bond type C=C lost 1 Bond type C-C gained 1 Bond type C=O gained 1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

composite	G2	2428
	G3	2436
	G3B3	2436
	G4	2439
	CBS-Q	2427

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Proton Affinities in kJ/mol

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	2794	2582	2582	2585	2585	2594	2577	2589	2592	2594	2576	2580	2597	2583	2581	2579	2577	2578	2580	2577
density functional	BLYP	2697
	B1B95	2689	2533	2533	2523	2523	2523	2506	2520	2522	2527	2502	2510		2511		2502	2503
	B3LYP	2724						2521						2531
	B3PW91	2726	2563	2563								2534					2533	2534		2534	2534
	mPW1PW91	2727	2563	2563	2552		2559	2537			2559	2534	2541		2543		2534	2534		2534	2534
	M06-2X	2682	2510	2510	2505	2502	2507	2486	2499	2500	2504	2482	2488	2503	2487		2482	2480		2483	2480
	PBEPBE											2499
	PBE1PBE	2720	2553	2553	2542	2543	2543	2526		2542	2548	2522	2529		2531		2523	2522		2523	2522
	HSEh1PBE	2720	2554	2554	2543			2526			2548	2522	2529		2531		2523	2522		2523	2522
	TPSSh	2724				2553						2534		2556				2533	2534		2533
	wB97X-D	2732	2564	2564	2554	2555	2561	2539		2554	2560	2537	2544		2547	2544	2536	2539	2540	2537	2539
	B97D3	2731																			2540
		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	2686	2465	2465	2435			2443			2457	2431			2451	2440		2435	2433		2434
	MP2=FULL	2686	2465	2465	2435		2471	2444			2462	2431			2454	2442		2440	2435		2439
	MP3					2483		2500				2496	2514	2535	2512					2502
	MP3=FULL		2497	2497	2477	2483	2523	2501	2497	2530	2518	2496	2514	2536	2515		2502	2505		2503
	B2PLYP	2711
	B2PLYP=FULL	2711
	B2PLYP=FULLultrafine	2711				2515								2530	2510
Configuration interaction	CID		2518	2518	2501	2508			2520			2518		2554	2533					2525
	CISD		2524	2524	2508	2514			2525			2521		2558	2536					2529
		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		2516	2516	2495	2505	2542	2518	2518	2548	2534	2515	2531		2531		2520			2521
	QCISD(T)																	2499
	QCISD(T)=FULL							2503				2496
Coupled Cluster	CCD		2497	2497	2476	2486	2524	2502	2499	2531	2516	2498	2514	2537	2514		2504			2504
	CCSD					2503	2540	2517	2516	2546	2533	2514	2530	2553	2530		2519			2520
	CCSD=FULL					2503					2538	2514	2530	2554	2533		2520			2521
	CCSD(T)					2490	2527	2503			2517	2496					2503
	CCSD(T)=FULL					2490						2495					2504
		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

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Proton Affinities in kJ/mol

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	2596	2594	2586	2580	2586	2586			2580
density functional	B1B95									2507
	B3LYP	2546		2538
	B3PW91									2539
	mPW1PW91									2539
	M06-2X									2485
	PBE1PBE									2527
	HSEh1PBE									2527
	wB97X-D	2558	2565	2549	2551	2550	2551			2543
Moller Plesset perturbation	MP2	2432	2437	2419	2424	2417	2416			2444
	MP2=FULL									2446
	MP3									2507
	MP3=FULL									2508
Configuration interaction	CID									2528
	CISD									2531
Quadratic configuration interaction	QCISD									2526
	QCISD(T)									2507
Coupled Cluster	CCD									2509
	CCSD									2524
	CCSD=FULL									2526
	CCSD(T)									2507

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.