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Research Fellows Directory

Fidel Alejandro Batista Romero

Dr Fidel Alejandro Batista Romero

Research Fellow


University of Bristol

Research summary

Enormous progress has been made in the development of quantum embedding theories that allow a small, important region to be modelled to high accuracy, even when it is connected to a complex chemical environment. Quantum embedding techniques go beyond the framework of the Nobel-prize-winning QM/MM framework by allowing coupling between system and environment to take account of quantum effects such as dispersion, exchange-repulsion and entanglement. Examples of systems where strong coupling to the environment plays an important role include in enzymological problems with active sites covalently bound to a larger protein environment; problems in surface science where reactivity or excitations of molecules take place near semi-conductor or metal surfaces; and in cases such as homogeneous transition-metal catalysis where the complexities of the electronic structure demand system partitions that cut very close to the reactive centre.

The aim of my work is to develop a novel embedding framework that captures the polarisation and screening effects that an environment exerts on excited states of a small subsystem. Electronic excitations in a chromophore in solution, or in a defect or impurity in a solid, invariably entail redistribution of electronic charge. In concert with this effect the environment adjusts to the new electronic state of the impurity, and this reorganisation is characterised by a slow component (in which ions or polar molecules rearrange themselves to stabilise the excited state of the impurity) and a fast component that arises from electronic reorganisation in the environment.

Interests and expertise (Subject groups)

Grants awarded

A quasiparticle approach to excited-state embedding

Scheme: Newton International Fellowships

Dates: Jan 2018 - Dec 2019

Value: £90,300