Quantum Control of Molecules: From Chemi-Ionization to Full Molecular Orientation Control

Fecha: martes, 11 de abril de 2023.
Hora: 10:00h.
Lugar: Seminario del Dpto. de Física Atómica, Molecular y Nuclear (Facultad de Ciencias, Sección Físicas, 3ª planta).

Ponente: Dr. Juan J. Omiste, Departamento de Química Física, Universidad Complutense de Madrid.

In this talk, we discuss two novel approaches to achieve full control over chemical reactions and molecular dynamics. Firstly, we present a study of chemi-ionization in collisions of two atoms in excited states, specifically Ne(3P2)-Ar and He*-He*. The collision energy of the reagents was tuned, and the orientation of the excited atoms relative to each other was fully specified by an external magnetic field. Chemi-ionization of the atoms in these conditions enables a detailed investigation of how the reaction proceeds, and provides a means to control the branching ratio between the two possible reaction outcomes. Secondly, we introduce a novel approach to attain full control over the rotational dynamics of asymmetric molecules using Quantum Optimal Control Theory (QOCT). Specifically, we make use of the coupling between an external electric field and the permanent dipole moment to manipulate the orientation of non-asymmetric molecules. Our research demonstrates that any axis of a non-asymmetric molecule can be oriented using QOCT. We provide evidence of the efficacy of our approach by utilizing 6-chloropyridazine-3-carbonitrile as a prototype example. Furthermore, we conduct a spectral analysis of the control field to gain a comprehensive understanding of the control mechanism and the underlying physical phenomena contributing to the molecular orientation control. Our work highlights the potential of these two approaches in designing novel chemical processes and manipulating molecular dynamics.