The theoretical study of molecular excited states is a topic of growing interest due to its potential applications in many areas. The development of faster computers and new methodologies has allowed to study increasingly large systems and also to broaden the traditionally static perspective of these studies, tackling the time evolution of the excited states. This is an area of interest for many possible PhD or master students working not only in theory but also in experimental photochemistry or photophysics. In our experience, with more than 10 years teaching this subject at master and doctorate level, this subject requires combining theory and practice for the students to fully understand the concepts and methods.
Excited state modelling is probably the area of quantum chemistry that requires more training. These calculations can rarely be run as a "black box". In fact these calculations require the detailed selection of the configurations and the careful analysis of their convergence. Thus, practical exercises are crucial to have an in depth insight into the methodology. For this reason, we believe that this topic perfectly suits the proposed structure of a course with an equal distribution of theory and practice.
The tutorial we propose on "Molecular Excited States" will be part of the European Master in Theoretical Chemistry and Computational Modelling (EMTCCM, see details at www.emtcccm.org) for first year Spanish Students, but this course is intended to be open to other participants not involved in the master. Our goal is to offer our teaching experience on this subject not only to the students doing the EMTCCM master in Spain, but also to other European master or doctorate students, favoring the reinforcement of the contacts with other masters and European initiatives.
The level of the course corresponds to master or doctorate students in the areas of physics and chemistry. For Spanish students of the EMTCCM master, this tutorial will be a part of a more general optional course on excited states. The tutorial will be organized for a maximum number of 40 students, from which 20 are expected to belong to the EMTCCM master. We have previous experience in the organization of similar schools in ZCAM in 2011, 2012 and 2013, sponsored by the master and the COST action CMT0702. To give an idea of the potential interest of this course, 41 students from 12 different European countries attended the tutorial in 2011, while 24 students from 10 different countries were registered in 2012 and 2013.
The tutorial will cover different aspects related with the characterization of excited states and their properties, the exploration of excited state potential energy surfaces, including conical intersections, as well as dynamics simulations. We intend to offer an overview of the different state of the art methods to characterize excited states in molecules. We will present a multidisciplinary approach including lectures on the fundamentals and use of quantum chemical methods for the prediction of the excited states energies and the examination of the topology of excited state potential energy surfaces together with techniques that allow running dynamics simulations considering simultaneously electronic and nuclear motion using these surfaces. Applications to physics and chemistry will be covered.
The tutorial will be organized in 10 theoretical lectures and 5 practical lessons in the computer lab. Theoretical lectures will be of 2 hours and practical sessions will last 4 hours. Two lectures will be devoted to general aspects of modern photochemistry. Four lectures will focus in the main protocols to evaluate the energy and properties of electronic excited states: Multiconfigurational and Time Dependent Density Functional Theory methods. The last four theoretical sessions will be devoted to dynamical aspects, using two different approaches: wave-packet propagations and ab initio molecular dynamics (Born-Oppenheimer and Ehrenfest dynamics).
Two practical sessions will cover the calculation of excited states using multiconfigurational methods. One session will focus in the practical aspects of TDDFT calculation of energies and spectra. The last two sessions will consider semiclassical and quantum dynamics simulations.