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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The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

XIV.K.1. (III.G.4.)

Transition State Energies

Please click on a reaction below.

Reaction	Reactants	↔	Products
Reaction 1	H2 + H	↔	H + H2
Reaction 2	CH3 + HF	↔	CH4 + F
Reaction 3	C2H4 + HCl	↔	CH3CH2Cl
Reaction 4	H2 + OH	↔	H2O + H
Reaction 5	N2 + OH	↔	N2O + H
Reaction 6	OH + O	↔	HO2
Reaction 7	H2 + NH2	↔	H + NH3
Reaction 8	CH3 + H2	↔	CH4 + H
Reaction 9	SiH3 + H2	↔	SiH4 + H
Reaction 10	HNC	↔	HCN
Reaction 11	H2 + PH2	↔	H + PH3
Reaction 12	H2 + HS	↔	H + H2S
Reaction 13	H2O + CH3	↔	CH4 + OH