Theoretical and Computational Chemistry

Benchmarking Density Functionals, Basis Sets, and Solvent Models in Predicting Thermodynamic Hydricities of Organic Hydrides

Authors

Abstract

Many renewable energy technologies, such as hydrogen gas synthesis and carbon dioxide reduction, rely on chemical reactions involving hydride anions. When selecting molecules to be used in such applications, an important quantity to consider is the thermodynamic hydricity, which is the free energy required for a species to donate a hydride anion. Theoretical calculations of thermodynamic hydricity depend on several parameters, mainly the density functional, basis set, and solvent model. In order to assess the effects of the above three parameters, we carry out hydricity calculations for a set of molecules with known experimental hydricity values, generate linear fits, and compare the R-squared, root-mean-squared error, and Akaike Information Criterion across different combinations of density functionals, basis sets, and solvent models. Based on these results we are able to quantify the accuracy of theoretical predictions of hydricity and recommend the parameters with the best compromise between accuracy and computational cost.

Content

Thumbnail image of Hydricity.pdf

Supplementary material

Thumbnail image of example_input.zip
Example input files
Example input files for each level of theory used. P01-P10 are TeraChem input files while P11 is a Q-Chem input file.
Thumbnail image of starting_structures.zip
Starting structures
.xyz files of the starting molecular structures.
Thumbnail image of tables_of_hydricity_values.zip
Tables of hydricity values
Tables containing all experimental and calculated hydricity values
Thumbnail image of lvlthry.txt
Levels of Theory
Table of all levels of theory used labeled by ID number
Thumbnail image of molecules.txt
Molecule information
Contains information about the charge and spin multiplicity of each molecule