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Adjusting the band gap energy of metal halide perovskite by anion exchange (CsPbBr3−yXy: X = Cl, Br, I) leads to optimal interfacial electron transfer from CsPbBr3−yXy to TiO2, and thus to improved photocatalytic hydrogen generation.

This work shows that S-atom substitution in phosphate, controls the directionality of hole transfer processes between base and sugar-phosphate backbone in DNA systems. The investigation combines synthesis, electron spin resonance (ESR) studies in supercooled homogeneous solution, pulse radiolysis in aqueous solution at ambient temperature and density functional theory (DFT) calculations of in-house synthesized model compound dimethylphosphorothioate (DMTP(O(−))=S) and nucleotide (5’-O-methoxyphosphorothioyl-2’-deoxyguanosine (G-P(O(−))=S)). ESR investigations show that DMTP(O(−))=S reacts with Cl(2)(•−) to form the σ(2)σ*(1) adduct radical -P-S∸Cl which subsequently reacts with DMTP(O(−))=S to produce [-P-S∸S-P-](−). -P-S∸Cl in G-P(O(−))=S undergoes hole transfer to Gua forming the cation radical (G(•+)) via thermally activated hopping. However, pulse radiolysis measurements show that DMTP(O(−))=S forms the thiyl radical (-P-S•) by one-electron oxidation which did not produce [-P-S∸S-P-](−). Gua in G-P(O(−))=S is oxidized unimolecularly by -P-S• intermediate in sub-picosecond range. DFT thermochemical calculations explain the differences in ESR and pulse radiolysis results obtained at different temperatures.

In this paper, the history, present status, and future of density-functional theory (DFT) is informally reviewed and discussed by 70 workers in the field, including molecular scientists, materials scientists, method developers and practitioners. The format of the paper is that of a roundtable discussion, in which the participants express and exchange views on DFT in the form of 300 individual contributions, formulated as responses to a preset list of 26 questions. Supported by a bibliography of 776 entries, the paper represents a broad snapshot of DFT, anno 2022.

Validation of prediction uncertainty (PU) is becoming an essential task for modern computational chemistry. Designed to quantify the reliability of predictions in meteorology, the calibration-sharpness (CS) framework is now widely used to optimize and validate uncertainty-aware machine learning (ML) methods. However, its application is not limited to ML and it can serve as a principled framework for any PU validation. The present article is intended as a step-by-step introduction to the concepts and techniques of PU validation in the CS framework, adapted to the specifics of computational chemistry. The presented methods range from elementary graphical checks to more sophisticated ones based on local calibration statistics. The concept of tightness, is introduced. The methods are illustrated on synthetic datasets and applied to uncertainty quantification data extracted from the computational chemistry literature., Accepted for publication in J. Chem. Phys

We review the alternative proposals introduced recently in the literature to update the standard formula to estimate the uncertainty on the mean of repeated measurements, and we compare their performances on synthetic examples with normal and non-normal error distributions.

International audience; The distribution of errors is a central object in the assesment and benchmarking of computational chemistry methods. The popular and often blind use of the mean unsigned error as a benchmarking statistic leads to ignore distributions features that impact the reliability of the tested methods. We explore how the Gini coefficient offers a global representation of the errors distribution, but, except for extreme values, does not enable an unambiguous diagnostic. We propose to relieve the ambiguity by applying the Gini coefficient to mode-centered error distributions. This version can usefully complement benchmarking statistics and alert on error sets with potentially problematic shapes.

International audience; Nucleation and growth of crystallites are induced by the shockwave of a single laser nanosecond pulse in highly supersaturated solutions of potassium nitrate (saltpeter). The kinetics of the turbidity resulting from the light scattering by the growing crystals is observed by time-resolved optical spectroscopy. With an optical path of 10 mm, we first focused on the early part of the growth under various conditions, but it is limited by the detection system to a few percent of the total growth. Remarkably, in this domain and for all supersaturated concentrations studied, the turbidity increases proportionally with time. This zero-order process with an accretion rate constant (k = 4.7 × 107 L mol–1 s–1) implies that the nuclei and growing crystals’ concentration remain constant. This concentration is determined from the final diameter of crystals that are observed to have a bipyramidal shape by transmission electron microscopy (TEM). Moreover, the number of accretion sites per crystal must be constant in this time range and they are identified as the apexes. In complement, the kinetics detected with shorter optical paths permits us to observe larger parts of the total growth (up to 35% with 1 mm of optical path). In this case, after the linear part, the turbidity increase is markedly accelerated, indicating that the number of accretion sites per crystal increases rapidly with the crystal size and that the edges and facet sites also fix the molecules. The complete analysis by a homogeneous kinetics model of the signals obtained under various conditions concludes to an anisotropic growth of the crystals with another accretion rate constant (k′ = 100 L mol–1 s–1) that is much lower on these edges and facet sites than on the apexes. However, this contribution becomes predominant only when the crystals develop to a larger size.

Context. Characterizing temperate (200–1000 K) super-Earth atmospheres is one of the future challenges in exoplanetary science. One of the major difficulties comes from the ubiquity of aerosols in these objects, which complicates the spectroscopic analyses. The knowledge gained on the Solar System is then crucial to better understand the chemical processes of exoplanet atmospheres. Aims. This work focuses on the impact of ion chemistry on molecular diversity in a specific Titan-like exoplanet atmosphere that would be dominated by molecular nitrogen. On the largest satellite of Saturn, Titan, ion chemistry is a major component of molecular growth that forms precursors for the observed photochemical organic hazes. Methods. Based on an experimental approach, we irradiated a gaseous mixture representative of a Titan-like atmosphere (N2-dominated with CH4) using an extreme-uv photon source (16.8 eV). Trace amounts of water vapor were added to the composition of the Titan-type gas mixture to simulate an exoplanet in the habitable zone. Results. A wide variety of molecules and ions have been detected and they cannot all be identified based on our current knowledge of the organic chemistry of planetary atmospheres (mostly N- and C-based chemistry). The presence of even trace amounts of H2O significantly broadens the product distribution, and H3O+ is found to be the most abundant ion. Conclusions. This work demonstrates the complexity of the chemistry within exoplanet atmospheres. Numerical models must consider oxygen chemistry and ion-molecule reactions in order to probe the habitability of a certain type of super-Earths. The abundance of H3O+ makes it a good candidate for future observations.

We present an automated data analysis procedure for clinical spectral-domain OCT, capable of correcting instrument-related hyperreflective artifacts, and its application to normal corneas. Quantitative parameters related to corneal transparency are extracted from 85 eyes.

Invited for the cover of this issue are the groups of Roman Dembinski, Mehran Mostafavi, and Amitava Adhikary at the Polish Academy of Sciences, Université Paris-Saclay, and Oakland University. The image depicts a doughnut as a way of illustrating the hole transfer process. Read the full text of the article at 10.1002/chem.202000247.

In the first part of this study (Paper I), we introduced the systematic improvement probability (SIP) as a tool to assess the level of improvement on absolute errors to be expected when switching between two computational chemistry methods. We developed also two indicators based on robust statistics to address the uncertainty of ranking in computational chemistry benchmarks: Pinv , the inversion probability between two values of a statistic, and Pr , the ranking probability matrix. In this second part, these indicators are applied to nine data sets extracted from the recent benchmarking literature. We illustrate also how the correlation between the error sets might contain useful information on the benchmark dataset quality, notably when experimental data are used as reference.

Uncertainty quantification (UQ) in computational chemistry (CC) is still in its infancy. Very few CC methods are designed to provide a confidence level on their predictions, and most users still rely improperly on the mean absolute error as an accuracy metric. The development of reliable uncertainty quantification methods is essential, notably for computational chemistry to be used confidently in industrial processes. A review of the CC-UQ literature shows that there is no common standard procedure to report nor validate prediction uncertainty. I consider here analysis tools using concepts (calibration and sharpness) developed in meteorology and machine learning for the validation of probabilistic forecasters. These tools are adapted to CC-UQ and applied to datasets of prediction uncertainties provided by composite methods, Bayesian Ensembles methods, machine learning and a posteriori statistical methods.

International audience; NMR measurements show that diethyl carbonate (DEC, a solvent with a low dielectric constant) solutions of LiClO4 contain (LiClO4)n oligomers. The reduction of these species by solvated electrons and pre-solvated electrons is followed by picosecond pulse radiolysis measurements. The data analysis shows that several anions absorbing in the NIR and visible range are formed after the 7 ps electron pulse. In contrast with THF solutions of LiClO4, the anionic monomer (LiClO4)- is not observed in DEC solutions. This is due to the fact that DEC is a non-polar solvent favoring the clustering of the monomers in the non-irradiated solution as shown by NMR results, and also due to the instability of the anionic monomer. The absorption spectra of the anionic dimer (LiClO4)2-, trimer (LiClO4)3- and tetramer (LiClO4)4- are clearly observed in NIR and in visible ranges. Compared to the results obtained for the same system in THF, and in agreement with simulated absorption spectra, the experimental results show that the absorption bands are shifted to the blue when n increases. The kinetics recorded for the molar LiClO4 solution indicate that the solute is only under the form of oligomers (LiClO4)n with a large n value and that the reduced species absorb weakly in the visible. Lastly, and contrarily to what is known for well separated ions in polar solvents, it is shown that the (LiClO4)n- anions are not stable with respect to self-reduction, leading to the decomposition of perchlorate anions. In this reaction the perchlorate anion ClO4- is reduced by the Li atom into a chlorate anion ClO3-. This is proved by the presence of ClO3- and of chlorinated species detected by mass spectrometry measurements in irradiated DEC solutions containing LiClO4.

The comparison of benchmark error sets is an essential tool for the evaluation of theories in computational chemistry. The standard ranking of methods by their Mean Unsigned Error is unsatisfactory for several reasons linked to the non-normality of the error distributions and the presence of underlying trends. Complementary statistics have recently been proposed to palliate such deficiencies, such as quantiles of the absolute errors distribution or the mean prediction uncertainty. We introduce here a new score, the systematic improvement probability (SIP), based on the direct system-wise comparison of absolute errors. Independently of the chosen scoring rule, the uncertainty of the statistics due to the incompleteness of the benchmark data sets is also generally overlooked. However, this uncertainty is essential to appreciate the robustness of rankings. In the present article, we develop two indicators based on robust statistics to address this problem: P_{inv}, the inversion probability between two values of a statistic, and \mathbf{P}_{r}, the ranking probability matrix. We demonstrate also the essential contribution of the correlations between error sets in these scores comparisons.

Molecular simulations are one of the most prominent discovery tools in science and engineering, widely adopted in applications ranging from drug discovery to materials design. The fidelity of the predictions of molecular simulations hinges on the reliability and accuracy of the chosen force fields. Thus, the quantification of uncertainties associated with the form of force fields and their parameters is a fundamental part of molecular modeling. This aspect has been rather overlooked in the past but constitutes today an active field of research. This review focuses on the data-driven Bayesian calibration of force fields. The calibration of molecular force fields is a very challenging task in the presence of an ever-increasing amount, type, and scale of reference data. Bayesian data analysis provides an invaluable tool to address this challenge, notably in the presence of model inadequacy. It enables a rigorous definition of uncertainties for the force fields and allows for data-driven robust predictions through molecular simulations. This chapter reviews recent methodological and algorithmic developments in Bayesian calibration of force fields and their application to atomic and molecular fluids. We discuss Bayesian approaches and their computational challenges followed by a description of target applications. We believe that the advances in Bayesian inference presented in this chapter would be valuable for a number of other fields in science and engineering that are revolutionized by data science.

The directionality of the hole-transfer processes between DNA backbone and base was investigated by using phosphorodithioate [P(S- )=S] components. ESR spectroscopy in homogeneous frozen aqueous solutions and pulse radiolysis in aqueous solution at ambient temperature confirmed initial formation of G.+ -P(S- )=S. The ionization potential of G-P(S- )=S was calculated to be slightly lower than that of guanine in 5'-dGMP. Subsequent thermally activated hole transfer from G.+ to P(S- )=S led to dithiyl radical (P-2S. ) formation on the μs timescale. In parallel, ESR spectroscopy, pulse radiolysis, and density functional theory (DFT) calculations confirmed P-2S. formation in an abasic phosphorodithioate model compound. ESR investigations at low temperatures and higher G-P(S- )=S concentrations showed a bimolecular conversion of P-2S. to the σ2 -σ*1 -bonded dimer anion radical [-P-2S - . 2S-P-]- [ΔG (150 K, DFT)=-7.2 kcal mol-1 ]. However, [-P-2S - . 2S-P-]- formation was not observed by pulse radiolysis [ΔG° (298 K, DFT)=-1.4 kcal mol-1 ]. Neither P-2S. nor [-P-2S - . 2S-P-]- oxidized guanine base; only base-to-backbone hole transfer occurs in phosphorodithioate.

Quantum machine learning models have been gaining significant traction within atomistic simulation communities. Conventionally, relative model performances are being assessed and compared using learning curves (prediction error vs. training set size). This article illustrates the limitations of using the Mean Absolute Error (MAE) for benchmarking, which is particularly relevant in the case of non-normal error distributions. We analyze more specifically the prediction error distribution of the kernel ridge regression with SLATM representation and L 2 distance metric (KRR-SLATM-L2) for effective atomization energies of QM7b molecules calculated at the level of theory CCSD(T)/cc-pVDZ. Error distributions of HF and MP2 at the same basis set referenced to CCSD(T) values were also assessed and compared to the KRR model. We show that the true performance of the KRR-SLATM-L2 method over the QM7b dataset is poorly assessed by the Mean Absolute Error, and can be notably improved after adaptation of the learning set.

International audience; Loss of corneal transparency, as occurs with various pathologies, infections, immune reactions, trauma, aging, and surgery, is a major cause of visual handicap worldwide. However, current means to assess corneal transparency are extremely limited and clinical and eye-bank practice usually involve a subjective and qualitative observation of opacities, sometimes with comparison against an arbitrary grading scale, by means of slit-lamp biomicroscopy. Here, we describe a novel objective optical data analysis-based method that enables quantifiable and standardized characterization of corneal transparency from depth-resolved corneal images, addressing the demand for such a means in both the laboratory and clinical ophthalmology setting. Our approach is based on a mathematical analysis of the acquired optical data with respect to the light attenuation from scattering processes in the corneal stroma. Applicable to any depth-resolved corneal imaging modality, it has been validated by means of full-field optical coherence tomographic microscopy (FF-OCT or FF-OCM). Specifically, our results on ex-vivo corneal specimens illustrate that 1) in homogeneous tissues, characterized by an exponential light attenuation with stromal depth (z), the computation of the scattering mean-free path (ls) from the rate of exponential decay allows quantification of the degree of transparency; 2) in heterogeneous tissues, identified by significant deviations from the normal exponential z -profile, a measure of exponential-decay model inadequacy (e.g., by computation of the Birge ratio) allows the estimation of severity of stromal heterogeneity, and the associated depth-dependent variations around the average ls enables precise localization of the pathology.

Computational chemistry has become an important complement to experimental measurements. In order to choose among the multitude of the existing approximations, it is common to use benchmark data sets, and to issue recommendations based on numbers such as mean absolute errors. We argue, using as an example band gaps calculated with density functional approximations, that a more careful study of the benchmark data is needed, stressing that the user's requirements play a role in the choice of an appropriate method. We also appeal to those who measure data capable of being used as a reference, to publish error estimates. We show how the latter can affect the judgment of approximations used in computational chemistry.

Lack of corneal transparency is a major cause of blindness worldwide. However, means to assess corneal transparency are limited and in current clinical and eye-bank practice usually involve a subjective and qualitative observation of opacities, sometimes with comparison against an arbitrary grading scale, by means of slit-lamp biomicroscopy. To address this unmet need, we have developed a method for corneal transparency assessment based on a new optical data analysis-based approach. Our method allows the objective extraction of quantitative parameters (including the scattering mean-free path, ls, a major indicator of scattering extent and thus of transparency of a medium) based on a physical model of corneal transparency and has been validated by laboratory experiments, using high-resolution, ex-vivo “full-field” optical coherence tomography (FF-OCT). Here, we apply our algorithm to depth-resolved spectral domain OCT (SD-OCT) images of in-vivo corneas and demonstrate the feasibility of our approach by means of four representative clinical cases. Specifically, we illustrate its potential in discriminating between the four clinical cases and, if applicable, deriving the scattering mean-free path as a quantitative measure of corneal transparency from objective analysis of stromal light backscattering (attenuation of the coherent mean) with SD-OCT. This measure may be related to, or expressed as, Strehl ratio reduction and thus retinal PSF broadening. As such, our approach not only has the potential to supply the demand for an objective means to quantify corneal transparency in the clinical setting, but also to create an association with visual function.

The detailed mechanism of the reaction between SCN

International audience; For a researcher, there is nothing more frustrating than the failure to reproduce major results obtained a few months back. The causes of such disappointments can be multiple and insidious. This phenomenon plays an important role in the so-called “research reproducibility crisis”.This book takes a current perspective onto a number of potentially dangerous situations and practices, to examplify and highlight the symptoms of non-reproducibility in research. Each time, it provides efficient solutions ranging from good-practices that are easily and immediately implementable to more technical tools, all of which are free and have been put to the test by the authors themselves.With this book written during a book sprint, students and engineers and researchers should find efficient and accessible ways leading them to improve their reproducible research practices.; Pour un chercheur, il n’y a rien de plus frustrant que l’impossibilité de reproduire des résultats majeurs obtenus quelques mois auparavant. Les causes de ce type de déconvenues sont multiples et parfois pernicieuses. Ce phénomène participe à ce que certains identifient comme une “crise de la reproductibilité de la recherche”.Cet ouvrage considère un ensemble de situations et de pratiques potentiellement dangereuses afin d’illustrer et de mettre en évidence les symptômes de la non-reproductibilité dans la recherche. À chaque fois, il propose un éventail de solutions allant de bonnes pratiques faciles et rapides à implémenter jusqu’à des outils plus techniques, tous gratuits et mis à l’épreuve par les auteurs eux-mêmes.Dans ce livre rédigé lors d’un book sprint, étudiants, ingénieurs et chercheurs devraient trouver des moyens efficaces et à leur portée pour améliorer leurs pratiques de la recherche reproductible.

In its introductory sections, the title article seems to assert that there is a failure of the method of propagation of uncertainties (PoU), when applied to a linearized Arrhenius model. In consequence, the PoU formula is replaced by an expression of the confidence limits that can be easily implemented in Excel. This letter explicits that the observed “failure” is in fact due to an improper use of PoU, neglecting the essential term involving the parameters covariance, and that the replacement formula is only an alternative expression of the correct PoU formula.

International audience; With the upcoming launch of space telescopes dedicated to the study of exoplanets, the Atmospheric Remote-Sensing Infrared Exoplanet Large-survey (ARIEL) and the James Webb Space Telescope (JWST), a new era is opening in exoplanetary atmospheric explorations. However, especially in relatively cold planets around later-type stars, photochemical hazes and clouds may mask the composition of the lower part of the atmosphere, making it difficult to detect any chemical species in the troposphere or understand whether there is a surface or not. This issue is particularly exacerbated if the goal is to study the habitability of said exoplanets and search for biosignatures. This work combines innovative laboratory experiments, chemical modeling, and simulated observations at ARIEL and JWST resolutions. We focus on the signatures of molecular ions that can be found in upper atmospheres above cloud decks. Our results suggest that H3+ along with H3O+ could be detected in the observational spectra of sub-Neptunes based on a realistic mixing ratio assumption. This new parametric set may help to distinguish super-Earths with a thin atmosphere from H2-dominated sub-Neptunes to address the critical question of whether a low-gravity planet around a low-mass active star is able to retain its volatile components. These ions may also constitute potential tracers to certain molecules of interest, such as H2O or O2, to probe the habitability of exoplanets. Their detection will be an enthralling challenge for the future JWST and ARIEL telescopes.

Thanks to the \textit{Cassini} spacecraft onboard instruments, it has been known that Titan's ionospheric chemistry is complex and the molecular growth is initiated through the photolysis of the most abundant species directly in the upper atmosphere. Among the pool of chemical compounds formed by the photolysis, N-bearing species are involved in the haze formation but the chemical incorporation pathways need to be better constrained.}\\ In this work, we performed low-pressure EUV photochemical laboratory experiments. The APSIS reactor was filled with a N$_2$/CH$_4$ (90/10\%) gas mixture relevant to the upper atmosphere of Titan. The cell was irradiated by using a EUV photon source at 73.6 nm {which has been difficult to produce in the laboratory for previous studies.}. The photoproducts (both neutral and ionic species) were monitored \textit{in situ} with a quadrupole mass spectrometer. The chemical pathways are explained by confronting experimental observations and numerical predictions of the photoproducts. \\ The most interesting result in this work is that methanimine was the only stable N-bearing neutral molecule detected during the experiments and it relies on N$_2^+$ production. This experimental result is in agreement with the relatively high abundance predicted by 1D-photochemical models of Titan's atmosphere and comforts methanimine as an intermediate towards the formation of complex N-bearing organic molecules.\\ {This experiment is only testing one part of the overall chemical scheme for Titan's upper atmosphere due to the selective wavelength but demonstrates the capability to probe the chemical pathways occurring in Titan's atmosphere by minimizing bias coming from wall surface reactions.}

We demonstrate the feasibility of deriving quantitative measures of corneal transparency from objective analysis of stromal light backscattering with full-field optical coherence tomography (FF-OCT), addressing an unmet need in ophthalmology.

The primary localization process of radiation-induced charges (holes (cation radical sites) and excess electrons) remains poorly understood, even at the level of monomeric DNA/RNA-models, in particular, in an aqueous environment. Herein, we report the first spectroscopic study of charge transfer occurring in radiolysis of aqueous uridine 5′-monophosphate (UMP) solutions and its components: uridine, uracil, ribose and phosphate. Our results show that: prehydrated electrons effectively attach to base site of UMP; the holes in UMP formed by either direct-ionization or via reaction of UMP with the radiation-mediated water cation radical (H(2)O(•+)) facilely localize on the ribose site, despite the fact that a part of them were initially created either on the phosphate or uracil. The nature of phosphate-to-sugar hole transfer is characterized as a barrierless intramolecular electron transfer with a time constant of 2.5 ns, while the base-to-sugar hole transfer occurs much faster, within 5 ps electron pulse.

The ultrafast radiolytic behavior of tributyl phosphate, TBP, has been investigated using 7 ps electron pulses with 7 MeV kinetic energy, from which two key species have been observed and characterized: the TBP solvated electron (eTBP–) and the TBP triplet excited state TBP* (3a) or its fragmentation products. The eTBP– exhibits a broad absorption band in the visible and near-infrared (NIR) spectrum, with a maximum beyond our 1500 nm detection limit. Nitromethane was used to scavenge eTBP– to confirm its absorption spectrum and to determine its associated rate coefficient, 1.0 × 1010 M–1 s–1. The electron’s molar extinction coefficients were found by an isosbestic method using biphenyl as a solvated electron scavenger. The time-dependent radiolytic yield of eTBP– was also determined directly from 7 ps to 7 ns and compared with those in water, tetrahydrofuran, and diethyl carbonate. In less than 10 ns, the decay is not due to the reaction with other solvent molecules and is instead predominantly due to the...

The reactivity of a series of commonly used halogenated compounds (trihalomethanes, chlorofluorocarbon, hydrochlorofluorocarbon, fluorocarbons, and hydrofluoroolefin) with hydroxide and oxygen anion is studied in a compact Fourier transform ion cyclotron resonance. O- is formed by dissociative electron attachment to N2 O and HO- by a further ion-molecule reaction with ammonia. Kinetic experiments are performed by increasing duration of introduction of the studied molecule at a constant pressure. Hydroxide anion reactions mainly proceed by proton transfer for all the acidic compounds. However, nucleophilic substitution is observed for chlorinated and brominated compounds. For fluorinated compounds, a specific elimination of a neutral fluorinated alkene is observed in our results in parallel with the proton transfer reaction. Oxygen anion reacts rapidly and extensively with all compounds. Main reaction channels result from nucleophilic substitution, proton transfer, and formal H2+ transfer. We highlight the importance of transfer processes (atom or ion) in the intermediate ion-neutral complex, explaining part of the observed reactivity and formed ions. In this paper, we present the first reactivity study of anions with HFO 1234yf. Finally, the potential of O- and HO- as chemical ionization reagents for trace analysis is discussed.

Pulse radiolysis was used to study the mechanism of HO(•)-induced polymerization of poly(3,4-ethylenedioxythiophene), PEDOT, in aqueous solution. A step-by-step mechanism has been found which involves a recurrent oxidation process by HO(•) hydroxyl radicals produced by water radiolysis. Furthermore, the cation radical, EDOT(•)(+), has been proposed as the promoter of the first step of polymerization. The determination of rate constants values and the attribution of transient and stable species were confirmed by molecular simulations and spectrokinetic analysis. Moreover, applying a series of electron pulses enabled in situ PEDOT polymerization. These polymers, which were characterized in solution or after deposition, form globular self-assembled structures with interesting conducting properties. Such a synthesis initiated for the first time by an electron accelerator gives us a glimpse of future promising industrial applications in the field of conducting polymers synthesis.