While a blue shift in the absorption spectra of particles with decreasing particle size is a sign of a delocalised excited state restricted in size by the volume of the particles, it is not a sign that this state necessarily only involves the inorganic core of the particles and is bulk-like. (5/N)

We also find that for most particles the optical gap is predicted to increase with decreasing particle size, even if the optical gap involves also the ligands. (4/N)

Only for nanoparticles with alkyl phosphines, phosphine oxides or amines as corner-capping ligands do we predict that the optical gap corresponds to an excitation that is primarily delocalised over the core with minimal contribution of the ligands, a true core-to-core bulk-like excitation. (3/N)

The ligands are found to often not be innocent spectators but actively involved in low-energy excitations including the optical gap. (2/N)

We finish with defect calculations, using both the Mott-Littleton and super-cell methods, on lithium battery materials inspired by papers like this pubs.acs.org/doi/10.1021/...

Then we use the same potentials to predict pressure-dependent polymorphism in bulk MgO by calculating the relative enthalpies of a set of potential polymorphs as a function of pressure.

We then get them to optimise the structure of the MgO molecule using GULP, as well as in excel using a very simple version of gradient descent (excel, because they don't all have used Python before), again to dispel the notion that the computer is a black box.

This in order to convince them that the computer is not a black box but instead simply solves some equations that they in principle can solve themselves by hand (for such a simple system).

We start students off by getting them to calculate the potential energy curve of a Mg-O molecule using both the computer (GULP) and pen and paper.

#compchem

For more details and how to register see: thomasyoungcentre.org/event/tyc-sy... #chemsky #compchem