Let’s Talk Science
qToM at Trinity develops and applies state-of-the-art methodology, novel when necessary, in order to gain a microscopic quantum-mechanical description of the complex electronic interactions ubiquitous in material systems of technological interest.
In particular, we specialise in developing electronic structure methods appropriate to larger systems, i.e., those at or approaching experimental length-scales, and those which strike a good compromise between computational tractability and accuracy.
We have a long-standing research strand on transition-metal physics and chemistry generally, which is both interesting and challenging for us due to the emergence of strong electronic correlation effects. Our studies in this area have been diverse, ranging from insulating oxides, to strongly-correlated metals and dilute magnetic semiconductors, through to small organometallic dyes, and up to biological metalloproteins. The methodology that we develop is, very generally, applicable to systems spanning a range like this.
We have developed, in collaboration, a comprehensive and sophisticated suite of extensions to the linear-scaling DFT+U code developed during David O’Regan‘s PhD, now including cluster DFT+DMFT including total-energies, a very flexible constrained DFT module, numerous methods for defining subspaces for special treatment based on atomic orbitals or optimised Wannier functions, PAW+U, Pulay forces, and numerous forms of corrective Hamiltonian, including Hund’s exchange.
Increasingly, we are working in the area of theoretical spectroscopy, simulating spectroscopies such as photoemission, optical absorption, and electron energy loss on a routine basis. For this, we use theories including TDDFT and many-body perturbation theory within the GW and related approximations.