The devil in the details: A tutorial review on some undervalued aspects of density functional theory calculations

Abstract

Density functional theory (DFT) has become ubiquitous for chemical applications in research and in education. The exact functional at the foundation of DFT is unfortunately unknown, and issues arise when choosing an approximation for a specific application. With this tutorial review, we tackle the selection problem and many related ones, such as the choices of a basis set and of an integration grid, that are often overlooked by occasional practitioners and by more experienced users as well. We offer a practical approach in the form of a commented notebook containing 12 experiences that can be run on a simple computer in just a few hours. We propose this review as a primary source for those who are willing to include DFT in their everyday research or teaching activities in a way that reflects the research advances of the field in the last couple of decades.

Reactions of nickel(0) with organochlorides, organobromides, and organoiodides: mechanisms and structure/reactivity relationships

“…Even modern desktop computers with multicore processors are often sufficient to tackle smaller problems in organometallic reaction mechanisms. A full discussion of the opportunities and pitfalls is beyond the scope of this manuscript, but we would encourage new users of density functional theory to consult some useful introductory references 11,12 and consider the level of theory applied to systems that are similar to those of interest. 13 If we were to offer two pieces of advice, these would be: (i) ensure that a dispersion treatment is used, either through the use of a functional that includes it (e.g.…”

Evaluation of density functional theory for a large and diverse set of organic and inorganic equilibrium structures

“…12 A fundamental limitation of the DFT formalism is the lack of a universal XC DFT functional, 13,14 which has led to a proliferation in the number of developed DFT methods over the past couple of decades. 15 Therefore, the validation of DFT functionals has become an important step before using DFT for calculating a given chemical property.…”

A Computational Protocol Combining DFT and Cheminformatics for Prediction of pH-Dependent Redox Potentials

“…It may seem surprising that B3LYP, which is the most popular but not particularly new or generally accurate functional, performs better for redox potentials than other methods reported to perform best in other more comprehensive benchmarks. The very popular combination of B3LYP with double-ζ polarized basis sets (6-31G* or similarly ADZP) is believed to be the cause of the error cancellations (errors due to the functional and to the basis set incompleteness are similar and of opposite sign) 50 that make it reasonably accurate in many cases, especially when including a dispersion correction such as D3. 51 In a few cases the potential prediction was found to be up to 0.4 V off the experimental value.…”