All the reseach tasks scheduled in the project proposal have been originally designed and planned by Principal Investigator (external collaborators contributed nothing to their design although they all approved the final version of the proposal), and they have never been funded and carried out before. Also, the presented results of preliminary studies have never been published before.
Scientific Goal of the Project:
Many of the experimental works refer to the concept of aromaticity by overusing the age-old electron bookkeeping rules known from the chemistry textbooks. Although this makes the work more attractive to the general community of chemists, it contributes to some extent toward lowering reputation of this beautiful concept which has arguably stagnated for many decades with a focus on qualitative rules describing the conditions for but do not fully rationalizing how important the (anti)aromatic (de)stabilization is and how it determines the electron-transport and energy-harnessing properties of conjugated materials. In this project we aim to push forward the theory of aromaticity to better understand the real cause and effects of the resonance electronic structure of molecular systems. The core objective of the project is to progress toward understanding of the first-principle rules that determine the electronic resonance structure of the mono-, poly-, and macrocyclic chemical species containing a system of conjugated bonds, and to develop new methodologies and strategies for predicting the evolution of the resonance electronic structure under the influence of magnetic field and along chemical reactions
. The long-term goal of the project is a profound paradigmatic change of the concept of aromaticity to reveal its true colors and unearth its real predictive power.
Objectives, Challenges, and Methodology:
All the research tasks in this project are organized in such a way that they provide answers to the following scientific questions: (1) How to extract from the molecular wavefunction the information about assignments of electrons into particular bonds, and how to translate this information into the 'chemical language'? (2) Are the complementary descriptions of the electron delocalization effect by the first-order population analysis and the SCF energy decomposition sufficient to capture the actual multidimensional character of the aromaticity concept? (3) How the dynamic and static electron correlation effects affect the kekulean and non-kekulean (e.g. cross-ring) delocalization effects in aromatic compounds? (4) What is the real role of the aromatic stabilization effects in the conjugated materials containing macrocyclic structures distorted by different factors including 1st and 2nd order Jahn-Teller effects, Herzberg-Teller coupling, strains, etc.? (5) Is it possible to predict the magnetic response from the ground-state wavefunction without explicit solving of the time-dependent Schrö-dinger equation, and what are the limits of the frontier orbital-topology rule applicability? Thus, the execution of the proposed research project requires cross-disciplinary approaches using knowledge from applied mathematics (information theory), theoretical and computational chemistry, physics and materials science, which makes it truly exciting multidisciplinary challenge. To guarantee the best expertise and resources available most of the research tasks will be carried out in close collaboration with the world-renowned experts (theoreticians and experimentalists) in the field of molecular aromaticity and materials science from Spain, Sweden, and USA. All the research tasks in this proposal will be carried out with partial support of the PL-Grid Infrastructure (Poland) and BSC-CNS (Spain), as well as the resources provided by Jagiellonian University and University of Girona. The most demanding calculations of high-accuracy one- and two-electron reduced densities will be performed using the purchased workstation with a unique specification. The state-of-the-art computational methods and experimental techniques will be used.
Justification for Establishing of a New Team:
The project proposal poses several fundamental and interdisciplinary questions concerning the electronic resonance structure and physico-chemical properties of different mono-, poly-, and macrocyclic compounds and conjugated materials, most of which have never been comprehensively investigated (like phthalocyanines and their B/N-doped derivatives, the 3D- and 4D-macrocycles recently proposed in the literature, and so on), or they have been a subject of heated debates in the literature. To make sure that all the key aspects of this interdisciplinary project can be tackled within the foreseen time a team consisting of PI and two PhD students will be composed. Since PI has never formally been a supervisor of PhD students (although in his previous research projects he led the teams in which he had successfully interacted with students and postdocs who are co-authors of PI's 18 publications) this seems like a reasonable way to start and carry out the research plan. Both PhD students will be trained to develop a strong theoretical background needed to carry out the first 3 research tasks of the project, and they both will be involved in programming of different capabilities and modules of the new software. In the more applied part of the project, PhD students will carry out the research sharing the expertise with each other but working independently. Candidates will be engaged following a competitive selection procedure described in details elsewhere in this project proposal.
Risk Analysis and Contingency Plans:
Since parts of the methodological aspects of the project proposal has been partially validated by using tentative scripts codes written by PI (except the research task 3), and because of the fact that the outcomes of preliminary studies within the more applicative part of the proposal are more than promising in the context of the scientific goals of the project, all the research tasks scheduled in the proposed work plan are classified as medium-risk tasks. In the case of the research task 3, two alternative strategies of the implementation of the eBOP formalism for the post-HF type wavefunctions will be considered to minimize the risk (one of these approaches has already been validated by one of the external collaborators of the project). In other cases, contingency plans and different alternative approaches (if needed) are described in working plans of the particular research tasks. The risk associated with the experimental part carried out by external collaborators is also classified as medium risk since a lot of (unpublished) experimental data has already been collected; on-surface synthesis and the AFM experiments associated with the annulene-to-porphine designing strategy to reveal the source of global aromaticity is of medium/high risk: in case of failure, the results of high-level computational studies would still be published in the JCR Q1 journal, but most likely not from the top of the list. Finally, the collaborative network of the world-wide recognized experts in the field of molecular aromaticity, computational and theoretical chemistry, organic synthesis and material science will surely minimize the risk the potential failure of the tasks in the second part of the project in the event of unforeseen circumstances.
(1) Development and implementation of the extended bond-orbital projection method for one-determinant wavefunctions of any type.
(2) Combining the bond-orbital projection formalism with the electronic hamiltonian decomposition within the framework of the self-consistent field method.
(3) Extension of the bond-orbital projection technique to the correlated wavefunctions.
(4) To be or not to be aromatic: degeneration, symmetry, topology, and the limits of the "4n+2" electron bookkeeping rule.
(5) Electrons move in mysterious pathways: delocalization vs ring current.
Impact of the Project Results:
The project will deliver novel methodology that holds the promise to open new directions in the field of molecular aromaticity, as well as tools and research-based knowledge that could support the design and synthesis of novel conjugated materials for artificial photosynthesis and photoinduced electron transfer, molecular photovoltaics, porphyrinoids with resonance-driven optical-mechanistic switches for nanoscience, nanotechnology and biomedicine, and many others. Also, the results of the project will hopefully provide the basis for an updated and more comprehensive IUPAC definition of the concepts of aromaticity and antiaromaticity. A tangible result of the research project will be new software, a website dedicated exclusively to the project outcomes, and scientific open-access papers published in reputed journals from the ISI Master Journal List.