Quantum tunneling and transient switching dynamics in molecular rotor architectures

Project funded by Fundação para a Ciência e a Tecnologia, I.P. (FCT) (FCT_CPCA_2023_01), grant 2023.10981.CPCA.A2. Funded amount: EUR 17,086, as stated by the source. Runs 2024-06-01 to 2025-05-31. Keywords: rotational spectroscopy, quantum tunneling, molecular structure, rotor dynamics, Exact sciences, Exact sciences/Physical sciences. Source: OpenAIRE Graph, from the funder's project data (collected by OpenAIRE on 2025-07-18); national funding data, not CORDIS. Abstract given by the source: With the devising of the first artificial light-driven molecular motors, inspired by molecular architectures of biological origin, great effort has risen to visualize, probe and ultimately influence their structural dynamics, leading to a tailored performance of these artificial molecular systems. Broadband rotational spectroscopy has recently emerged in the portfolio of experimental techniques to tackle complex systems in the molecular nanotechnology domain because of its unique skill-set when paired in tandem with quantum chemistry calculations. From an experimental perspective, rotational spectroscopy has a unique ability to solve molecular structures in complex mixtures, without prior separation of its components. From the computational perspective, quantum chemistry methods are employed to determine the rotational pattern of each conformation in the spectrum, i.e., the structure of a molecular rotor at each mechanical step. Most synthetic molecular machines, although driven by quantum processes, exhibit classical kinetics, whereas operation by quantum tunneling motion is largely elusive. In recent attempts to understand the intramolecular dynamics of functionalized molecular rotors based on sandwich compounds using rotational spectroscopy, we stumbled upon spectral signatures of quantum tunneling emerging in a metallocene-based rotary system. This is a highly unexplored category of molecular motors, and one that could help us better understand the governing aspects when crossing the frontier of classical nano-motor motion to quantum tunneling motion in molecular nanotechnology. Line splitting in rotational spectra due to quantum tunneling is not new, but is unprecedented within this framework. With the support of state-of-the-art high-performance computing resources, we aim to explore tunneling in rotary switches and motors and pave the way into an unexplored arena in this research realm.

Original source.

Source: OpenAIRE Graph: projects of national funders, OpenAIRE, from the project data of Fundação para a Ciência e a Tecnologia, I.P. (FCT). Retrieved 2026-10-28. Licence: Creative Commons Attribution 4.0 (OpenAIRE Graph). Selected metadata, adapted presentation; the publisher's record is authoritative. No endorsement by the source is implied. Licence: Creative Commons Attribution 4.0 (CC BY 4.0).

AI-assisted summary: The project "Quantum tunneling and transient switching dynamics in molecular rotor architectures" is funded by FCT with a grant of EUR 17,086, running from June 1, 2024, to May 31, 2025. It focuses on rotational spectroscopy and molecular dynamics in nanotechnology. Suggested technology pillar: sensing. Generated by AI from the public source text; it may contain errors and the original source is authoritative.