ELOTE now works with Open-Shell systems

I ran a TD-DFT calculation on a platinum complex, fed the log file to ELOTE, and got only half an answer. The molecular orbital composition table printed just fine, every orbital with its atomic percentages. But the excited-state analysis, the whole point of the exercise, came back empty. The CSV had a header and nothing underneath. No transitions, no MLCT/LMCT labels, no summary table.

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What Makes a Silane Good at Reducing Phosphine Oxides? A New Paper in Eur. J. Inorg. Chem.

Some of the most useful reactions in a synthetic chemist’s toolbox — the Wittig, the Appel, the Mitsunobu, the Staudinger, have a common problem: they yield stoichiometric piles of phosphine …

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Behold the SpudCell

science.org

ELOTE: Making Sense of Your TD-DFT Excited States

If you have ever run a TD-DFT calculation in Gaussian and stared at the output wondering exactly what each excited state is made of — which orbitals, on which atoms, with what percentage — this pos…

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25th edition of the Mexican Meeting on Theoretical Physical Chemistry (RMFQT)

For over a quarter of a century, the Mexican Meeting on Theoretical Physical Chemistry (RMFQT) has served primarily as a national forum, with an increasingly ...

link.springer.com

Absorption and Emission Spectra with Gaussian 16

In photosynthesis research, emission spectra—particularly chlorophyll fluorescence—are not merely complementary to absorption measurements but are often more informative. While absorption spectra i…

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Absorption and Emission Spectra with Gaussian 16

In photosynthesis research, emission spectra—particularly chlorophyll fluorescence—are not merely complementary to absorption measurements but are often more informative. While absorption spectra indicate which wavelengths are harvested, emission spectra reveal the fate of that energy, providing direct insight into its partitioning between photochemistry, heat dissipation, and fluorescence. In this way, they serve as sensitive probes of energy transfer efficiency among pigments and of the functional state of the photosystems.

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Can Frustrated Lewis Pairs Really Split Water? A New Paper in Inorg. Chem.

Obtaining hydrogen from water is one of those topics that attracts lots of attention from many fronts in chemistry; on paper, it can be clean, elegant, and deceptively simple. In practice, however, water is stubborn and breaking it apart requires catalysts, large energy inputs, or clever chemistry that juggles thermodynamics and kinetics. Among the many clever ideas proposed over the last decade, …

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One electron C-C bond or Weak Interaction? New paper in PCCP

The compound spiro-dibenzocycloheptatriene (figure 1) made headlines a year ago by claiming that the ipso carbon atoms across the molecule were bound together by a single electron σ bond. This is truly a seductive idea: that somewhere out there, in the shadows of open-shell aromatics, carbon atoms might form a single-electron σ-bond — a unicorn of bonding, indeed. Since bold claims require bold scrutiny, we went ahead and dissected the electronic structure of the radical molecule in question with all the tools at our disposal; We also analyzed that of the neutral complex from where it was derived and also the double cation to analyze the consequences of removing the alleged electron holding such an unusual interaction, for if this C-C bond truly exists, it should alter the interaction energy between the fragments in a way consistent with a real σ bond.

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Bond Dissociation Energy with Gaussian16

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. In this tutorial we're going to calculate the C-H bond dissociation energy (BDE) in the methane (CH4) molecule, one of the strongest aliphatic bonds in organic chemistry.

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The man of MOFs and more

Nature Reviews Chemistry - Ahead of his 60th birthday, Omar Yaghi discussed his life in science so far and where he believes is the exciting space for future developments.

rdcu.be

Is Quantum Chemistry aligned with the Copenhagen or the Many Worlds interpretation of Quantum Mechanics?

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 being the discipline that has arguably done the most to turn quantum mechanics into a practical, predictive science.

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Unrecognized potential number 6 in GetPot

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. This error shows up when reading an external basis set and looks like this (color emphasis mine): Rotational constants (GHZ): 0.0492351 0.0073969 0.0065324 Leave Link 202 at Tue Sep 30 16:14:43 2025, MaxMem= 104857600 cpu: 1.5 elap: 0.2 (Enter /tmpu/scunam/7/gaussian-2016.C01/g1/g16/l301.exe) General basis read from cards: (5D, 7F) ====================================================================================================== Pseudopotential Parameters ====================================================================================================== Center Atomic Valence Angular Power Number Number Electrons Momentum of R Exponent Coefficient SO-Coeffient ====================================================================================================== Unrecognized potential number 6 in GetPot.

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Julieta Fierro: "La ciencia nos demuestra que no tenemos la verdad"

YouTube video by Aprendemos juntos Mex

youtu.be

Using DensToolKitViewer to get the best viewpoint

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. Installation and main controls were already covered in a previous post, as well as an update for ease of use. We use the file…

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Installing and uninstallng DensToolKitViewer

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. For this, execute the following commands…

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