The strength of a chemical bond can be defined as the change in enthalpy when a bond is homolytically broken into two radicals. Bond dissociation energy is thus the measure of the strength of a bond and, while it is temperature dependent, it can be calculated by DFT or ab initio methods.

2025 was declared by UNESCO as the International Year of Quantum Sciences, bringing a lot of celebrations, however much of the discourse is dominated by physicists and quantum technologists, some of which proclaim the dawn of the new “quantum revolution”. Yet, amid the excitement, I can’t help but notice that quantum chemistry remains underrepresented, despite […]

Unrecognized potential number 6 in GetPot A rather silly error in Gaussian, but one that seems to be common and to which I haven’t found any posted solutions, so here goes mine.

In this tutorial, we shall prepare a figure using DensToolKitViewer 2.1.0 (or later) to select the viewing angle of the molecule, for whenever the default view isn’t the optimal viewpoint or to get various for comparison.

The new DensToolKitViewer just got even better! So, if you want to update DTKViewer to make the most of the new features, in this tutorial we shall compile and install DensToolKitViewer. We provide the explicit steps to compile under Ubuntu and under MacOSX. We will assume that the git repo is cloned in /home/your_username/Downloads.

Preparing publication quality images from your calculations is essential. To pre-visualize images to get the best orientations of your molecule, DTK2.0 includes two options: a new GUI called DensToolKitViewer and DTKQDMol.

DensToolKit2 is a versatile open-source, cross-platform, suite of programs for analyzing electronic densities calculated from various sources and getting cool plots for some of the most popular scalar fields out there, such as electron densities, spin densities, visualizing critical points, or investigating complex topologies of noncovalent interactions, DensToolKit2 provides an integrated, script-friendly suite for analyzing electron densities

The Grignard addition is one of those reactions you learn during your first year of Organic chemistry and probably the last you forget when you become a computational chemist. It was Victor Grignard who became one of the earliest Nobel Laureate in Chemistry ever, and I know it took me a while to recognize it as an organometallic reaction. But the Grignard reaction is far from simple and its versatility keeps it as a rich source of study.

Computational chemistry is a field that thrives on innovation, precision, and the ability to tackle complex problems. With the rise of artificial intelligence (AI) and machine learning (ML), tools like DeepSeek are becoming indispensable for researchers and students alike.

Calculating reaction constants, in the correct physical way, requires accurate thermodynamic calculations involving solvation/desolvation energies at high levels of theory, because free energy deviations lower than 1 kcal/mol lead to reaction constant values off by an order of magnitude.

There are basically two kinds of electron correlation: static and dynamic.