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
tetraiodomethane	CI4	→	CH+	Methylidyne cation

Bonding changes
Bond type C-I lost 4 Bond type H-C gained 1

Proton Affinities (kJ/mol)

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Proton Affinities in kJ/mol

Methods with predefined basis sets

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Proton Affinities in kJ/mol

Methods with standard basis sets

		STO-3G	3-21G	3-21G*
hartree fock	HF	-71945721	-72335899	-72336617
density functional	BLYP	-71967036	-72364608	-72365384
	B1B95	-71977893	-72373661	-72373661
	B3LYP	-71968462	-72364655	-72365419
	B3PW91	-71970148	-72365761	-72366528
	mPW1PW91	-71974133	-72369222	-72369986
	M06-2X			-72369347
	PBEPBE	-71961867	-72358354	-72359137
	wB97X-D			-72366793
	B97D3		-72406220
		STO-3G	3-21G	3-21G*
Moller Plesset perturbation	MP2	-71945953	-72336382	-72338002
	MP2=FULL	-71945953	-72336490	-72338182
	MP4		-72336410
Configuration interaction	CID		-72336290	-72337691
	CISD		-72336297	-72337696
		STO-3G	3-21G	3-21G*
Quadratic configuration interaction	QCISD		-72336371	-72338003
Coupled Cluster	CCD		-72336358	-72337984
		STO-3G	3-21G	3-21G*

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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	-117452		-117449		-116882	-117081			-3115301
density functional	B3LYP	-120042		-120035		-119482	-119813			-3127490
	PBEPBE									-3126462
Moller Plesset perturbation	MP2	-117857		-117865		-117321	-117510			-3120803

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.