Leonardo Duarte holds a PhD in Chemistry from the University of Campinas (UNICAMP, 2023), where he defended the thesis "Chemistry of Molecular Vibrations", and completed a postdoctoral research within the Applied Computational Chemistry Group at the University of São Paulo (USP). His academic trajectory includes positions as a visiting researcher at the University of Manchester (UK, 2019) and the University of Coimbra (Portugal, 2024). Specializing in Physical Chemistry and Theoretical Chemistry, his research focuses on the study of infrared induced reactions, the development of models for Intramolecular Vibrational Energy Redistribution (IVR), and the Quantum Theory of Atoms in Molecules (QTAIM). He works in collaboration with leading groups in cryospectroscopy and molecular modeling, exploring topics such as quantum tunneling, chemometrics, and molecular dynamics applied to complex chemical systems.
RESEARCH, TEACHING, or OTHER INTERESTS
Physical and Theoretical Chemistry, Spectroscopy, General Chemistry
34
Scopus Publications
253
Scholar Citations
10
Scholar h-index
10
Scholar i10-index
Scopus Publications
NIR excitation-driven conformational isomerizations of thymol and carvacrol isolated in a nitrogen cryomatrix Leonardo J. Duarte, Cláudio M. Nunes, Ataualpa A. C. Braga, R. Fausto, A. J. Lopes Jesus Physical Chemistry Chemical Physics, 2026 Vibrationally induced rotamerization of thymol and carvacrol in an N 2 matrix: 2νOH excitation switches the hydroxyl orientation, while the isopropyl conformation remains unchanged, revealing OH torsion as the main pathway for energy redistribution.
Out-of-plane symmetry constraints for in-plane bending vibrations Vinicius Martinelli, Leonardo José Duarte, Luciano Nassif Vidal, Wagner Eduardo Richter Vibrational Spectroscopy, 2026 Whenever the dipole moment derivatives of out-of-plane bending vibrations in planar molecules are described in terms of atomic charges and their changes (either called charge transfer , C T , or charge fluxes , C F ), a constraint arises from the symmetry of the normal coordinate, requesting the charge transfer term to vanish, i.e., C T = 0 . This was first reported in 1989 by Dinur & Hagler and no exception has been found to this date. In this work, we show that the aforementioned symmetry constraints in planar molecules are, in fact, a special case within a more general one in which a given vibration is symmetric with respect to a given molecular plane of symmetry. This general case does not depend on the vibration being out-of-plane or in-plane bendings, nor on the molecule being planar or not. Nonetheless, whereas in the general case only the atoms lying on a symmetry plane will show C T = 0 , for out-of-plane vibrations of planar molecules all atoms will show C T = 0 simultaneously because all atoms belong to that plane, making the overall C T = 0 too. The argument is grounded on symmetry elements and their mathematical properties, while numerical examples are also presented and discussed.
Energetic Origins of the Hydrogen-Bond Redshift: IQA Partitioning of Normal Mode Force Constants Leonardo J. Duarte, Erick H. S. Alves, Ataualpa A. C. Braga Journal of Physical Chemistry A, 2025 The redshift of the D–H (where D represents the H donor group containing F, O, N) bond stretch normal coordinate is notable evidence of a hydrogen-bonded system. Upon the formation of the hydrogen bond, electron density is transferred from the acceptor moiety of the complex to the hydrogen atom donor, causing an elongation of the D–H bond and a reduction of the force constant. Within the orbital paradigm of chemistry, the redshift of the D–H stretch frequency is caused by the donation of electrons from the base lone pair to the antibonding, σ*, orbital of the D–H bond. The increased electron population of the antibonding orbital is, therefore, responsible for the decrease in the force constant and, consequently, for the redshift. In this work, we present a description of the H-bond redshift in terms of the electron density, substituting the molecular orbital theory interpretation with the Quantum Theory of Atoms in Molecules with the Interacting Quantum Atoms (IQA) energy decomposition scheme. The results herein suggest that the energetic origin of the redshift depends on the acid structure. When H2O acts as a H donor, the redshift is mostly determined by the intratomic and exchange–correlation, whereas the redshift of the HF stretch is caused primarily by the Coulomb contribution. The H acceptor molecule modulates the amount of variation in the above-mentioned cases. The better the acceptor, the greater the variation in the IQA contribution to the force constant.
Enantioselective Synthesis of 3,3-Disubstituted-2,3-dihydrobenzofurans by Intramolecular Heck-Matsuda/Carbonylation/Stille Coupling Luiz Paulo Melchior de Oliveira Leão, Otto Daolio Köster, Leonardo José Duarte, Ataualpa Albert Carmo Braga, Carlos Roque Duarte Correia Journal of Organic Chemistry, 2025 The enantioselective one-pot synthesis of 3,3-disubstituted-2,3-dihydrobenzofuran was developed via a strategy involving a palladium-catalyzed Heck-Matsuda reaction, followed by subsequent carbonylation and/or an organotin transmetalation step employing chiral N,N ligands. The one-pot reaction requires mild conditions and tolerates a wide range of functional groups. This method provides straightforward access to a diverse array of enantioenriched dihydrobenzofurans bearing a ketone or an alkyl side chain adjacent to the generated quaternary stereogenic center in yields up to 91% and er up to 99:1.
1H NMR Mixture Design-Fingerprints and ASCA Analysis in Ilex paraguariensis: Model Stability in Search of a Global Metabolome Gustavo Galo Marcheafave, Elis Daiane Pauli, Cláudia Domiciano Tormena, Leonardo José Duarte, Ivar Wendling, Miroslava Rakocevic, Amanda Lemos Quintela, Maria de Fátima Costa Santos, Cláudio Francisco Tormena, Ieda Spacino Scarminio, Roy Edward Bruns Analytical Chemistry, 2023 The effects of experimental repetitions and solvent extractors on the 1H NMR fingerprinting of yerba mate extracts, obtained from two genders and two light environments, were analyzed in-depth by ANOVA–simultaneous component analysis (ASCA). Different solvents were used according to a mixture design based on ethanol, dichloromethane, and hexane and their combinations. The number of experimental repetitions significantly affected the ASCA results. Increasing repetitions led to decreases in the percentage effect variance values and an increase in the percentage residual variance. However, secondary sexual dimorphism, light availability, and their interaction effects became more significant with decreasing p-values at or above the 95% confidence level. The choice of a solvent extractor significantly affects the chemical profile and can lead to distinct conclusions regarding the significance of effect values. Pure solvents yielded different conclusions about the significance of factorial design effects, with each solvent extracting unique metabolites and maximizing information for specific effects. However, the use of binary solvent mixtures, such as ethanol–dichloromethane, proved more efficient in extracting sets of compounds that simultaneously differentiate between different experimental conditions. The mixture design–fingerprint strategy provided satisfactory results expanding the range of extracted metabolites with high percentage of residual variances and low explained percentage effect variances in the ASCA models. Ternary and even higher-ordered mixtures could be good alternative extracting media for work-intensive procedures. Our study underscores the significance of experimental design and solvent selection in metabolomic analysis, improving the accuracy, robustness, and interpretability of metabolomic models, leading to a better understanding of the chemical composition and biological implications of plant extracts.
Out-of-plane symmetry constraints for in-plane bending vibrations V Martinelli, LJ Duarte, LN Vidal, WE Richter Vibrational Spectroscopy, 103908 , 2026 2026
NIR excitation-driven conformational isomerizations of thymol and carvacrol isolated in a nitrogen cryomatrix LJ Duarte, CM Nunes, AAC Braga, R Fausto, AJL Jesus Physical Chemistry Chemical Physics 28 (18), 11341-11352 , 2026 2026
Comparison of parametric and permutation t spectral representations for determining individual metabolite abundances from factorial design spectra LJ Duarte, GG Marcheafave, ED Pauli, IS Scarminio, RE Bruns Chemometrics and Intelligent Laboratory Systems, 105622 , 2025 2025
Matrix isolation of vapors from 1, 2, 4-triazolium salts: Exploring the generation of Nheterocyclic carbenes T Caneca, E Ntungwe, LJ Duarte, AJL Jesus, CM Nunes, R Fausto Journal of Molecular Structure 1345, 143058 , 2025 2025
Significance determination of individual metabolic abundance changes owing to environmental impacts: Factorial design t-distribution spectral representations GG Marcheafave, LJ Duarte, ED Pauli, IS Scarminio, RE Bruns Chemometrics and Intelligent Laboratory Systems 263, 105413 , 2025 2025 Citations: 1
Energetic Origins of the Hydrogen-Bond Redshift: IQA Partitioning of Normal Mode Force Constants LJ Duarte, EHS Alves, AAC Braga The Journal of Physical Chemistry A 129 (28), 6281-6288 , 2025 2025 Citations: 4
Enantioselective Synthesis of 3, 3-Disubstituted-2, 3-dihydrobenzofurans by Intramolecular Heck-Matsuda/Carbonylation/Stille Coupling LPMO Leao, OD Koster, LJ Duarte, AAC Braga, CRD Correia The Journal of Organic Chemistry 90 (26), 8835-8845 , 2025 2025 Citations: 4
Selective IR-induced conformational changes of Carvacrol in solid N2 matrix LJ Duarte, AJL Jesus, CM Nunes, AAC Braga, R Fausto Anais , 2025 2025
A protocol for the investigation of the intramolecular vibrational energy redistribution problem: the isomerization of nitrous acid as a case of study LJ Duarte, CM Nunes, R Fausto, AAC Braga Physical Chemistry Chemical Physics 27 (7), 3685-3700 , 2025 2025 Citations: 2
A protocol for the investigation of the IVR problem: The isomerization of HONO as a case of study LJ Duarte, CM Nunes, R Fausto, AAC Braga ChemRxiv 2024 (1025) , 2024 2024
IR intensities for out-of-plane vibrations at planar transition state structures: The NX3 series WE Richter, LJ Duarte Vibrational Spectroscopy 131, 103660 , 2024 2024 Citations: 2
Theoretical insights on the unexpected lability of Ru (III)(phtpy) Cl3: ligand-metal interactions through the lenses of DFT and TD-DFT LG Randolli, TM Mizumoto¹, LJ Duarte¹, K Araki¹, AAC Braga Proceedings , 2024 2024
Dissecting methanol adsorption on H-ZSM-5: a multiscale exploration using QM/QM TM Mizumoto, LJ Duarte, AAC Braga Anais , 2024 2024
Electronic Density Changes for Non-Equilibrium Molecular Geometries: A Charge–Charge Transfer–Dipolar Polarization Model LJ Duarte, WE Richter, RE Bruns Elsevier , 2024 2024
1 H NMR Mixture Design–Fingerprints and ASCA Analysis in Ilex paraguariensis : Model Stability in Search of a Global Metabolome GG Marcheafave, ED Pauli, CD Tormena, LJ Duarte, I Wendling, ... Analytical Chemistry 95 (46), 16850-16860 , 2023 2023 Citations: 5
Characteristic Substituent Effect Model for the Infrared Intensities of the X 2 CY (X = H, F, Cl, Br; Y = O, S) Molecules LJ Duarte, WE Richter, RE Bruns The Journal of Physical Chemistry A 127 (14), 3114-3122 , 2023 2023
Chemistry of molecular vibrations= Química de vibrações moleculares LJ Duarte [sn] , 2023 2023
Energetic origins of force constants: adding a new dimension to the Hessian matrix via interacting quantum atoms LJ Duarte, RE Bruns The Journal of Physical Chemistry A 126 (48), 8945-8954 , 2022 2022 Citations: 5
Infrared intensities of : a true challenge for DFT methods WE Richter, LJ Duarte Journal of Molecular Modeling 28 (10), 301 , 2022 2022
An Interacting Quantum Atoms (IQA) and Relative Energy Gradient (REG) Analysis of the Anomeric Effect D Khan, LJ Duarte, PLA Popelier Molecules 27 (15), 5003 , 2022 2022 Citations: 4
MOST CITED SCHOLAR PUBLICATIONS
Contributions of IQA electron correlation in understanding the chemical bond and non-covalent interactions AF Silva, LJ Duarte, PLA Popelier Structural Chemistry, 1-13 , 2020 2020 Citations: 45
Are “GAPT charges” really just charges? WE Richter, LJ Duarte, RE Bruns Journal of chemical information and modeling 61 (8), 3881-3890 , 2021 2021 Citations: 23
Atomic polarizations, not charges, determine CH out-of-plane bending intensities of benzene molecules LJ Duarte, RE Bruns The Journal of Physical Chemistry A 122 (51), 9833-9841 , 2018 2018 Citations: 17
Infrared intensification and hydrogen bond stabilization: Beyond point charges LJ Duarte, AF Silva, WE Richter, RE Bruns The Journal of Physical Chemistry A 123 (30), 6482-6490 , 2019 2019 Citations: 15
Review of experimental GAPT and infrared atomic charges in molecules WE Richter, LJ Duarte, AF Silva, RE Bruns Journal of the Brazilian Chemical Society 27, 979-991 , 2016 2016 Citations: 15
Electrostatics Explains the Reverse Lewis Acidity of BH 3 and Boron Trihalides: Infrared Intensities and a Relative Energy Gradient (REG) Analysis of IQA Energies LJ Duarte, WE Richter, RE Bruns, PLA Popelier The Journal of Physical Chemistry A 125 (39), 8615-8625 , 2021 2021 Citations: 14
Atomic charge and atomic dipole modeling of gas-phase infrared intensities of fundamental bands for out-of-plane CH and CF bending vibrations WE Richter, LJ Duarte, RE Bruns Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 251, 119393 , 2021 2021 Citations: 14
Unavoidable failure of point charge descriptions of electronic density changes for out-of-plane distortions WE Richter, LJ Duarte, RE Bruns Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 271, 120891 , 2022 2022 Citations: 13
FTIR and dispersive gas phase fundamental infrared intensities of the fluorochloromethanes: Comparison with QCISD/cc-pVTZ results LJ Duarte, AF Silva, WE Richter, RE Bruns Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 205, 269-275 , 2018 2018 Citations: 11
Electronic Distribution of S N 2 IRC and TS Structures: Infrared Intensities of Imaginary Frequencies LJ Duarte, RE Bruns Journal of chemical theory and computation 18 (4), 2437-2447 , 2022 2022 Citations: 10
AC/DC Analysis: Broad and Comprehensive Approach to Analyze Infrared Intensities at the Atomic Level WE Richter, LJ Duarte, LN Vidal, RE Bruns The Journal of Physical Chemistry A 125 (15), 3219-3229 , 2021 2021 Citations: 9
FTIR and dispersive gas phase absolute infrared intensities of hydrocarbon fundamental bands LJ Duarte, RE Bruns Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 214, 1-6 , 2019 2019 Citations: 9
QTAIM-based characteristic group infrared intensities of amino acids and their transference to peptides AF Silva, LJ Duarte, RE Bruns The Journal of Physical Chemistry A 120 (42), 8387-8399 , 2016 2016 Citations: 7
Probing the robustness of the charge-charge transfer-dipolar polarization model and infrared intensities AF Silva, LJ Duarte, RE Bruns Journal of molecular modeling 24 (7), 182 , 2018 2018 Citations: 6
1 H NMR Mixture Design–Fingerprints and ASCA Analysis in Ilex paraguariensis : Model Stability in Search of a Global Metabolome GG Marcheafave, ED Pauli, CD Tormena, LJ Duarte, I Wendling, ... Analytical Chemistry 95 (46), 16850-16860 , 2023 2023 Citations: 5
Energetic origins of force constants: adding a new dimension to the Hessian matrix via interacting quantum atoms LJ Duarte, RE Bruns The Journal of Physical Chemistry A 126 (48), 8945-8954 , 2022 2022 Citations: 5
Qtaim atomic charge and polarization parameters and their machine-learning transference among boron-halide molecules LJ Duarte, RE Bruns The Journal of Physical Chemistry A 124 (17), 3407-3416 , 2020 2020 Citations: 5
Energetic Origins of the Hydrogen-Bond Redshift: IQA Partitioning of Normal Mode Force Constants LJ Duarte, EHS Alves, AAC Braga The Journal of Physical Chemistry A 129 (28), 6281-6288 , 2025 2025 Citations: 4
Enantioselective Synthesis of 3, 3-Disubstituted-2, 3-dihydrobenzofurans by Intramolecular Heck-Matsuda/Carbonylation/Stille Coupling LPMO Leao, OD Koster, LJ Duarte, AAC Braga, CRD Correia The Journal of Organic Chemistry 90 (26), 8835-8845 , 2025 2025 Citations: 4
An Interacting Quantum Atoms (IQA) and Relative Energy Gradient (REG) Analysis of the Anomeric Effect D Khan, LJ Duarte, PLA Popelier Molecules 27 (15), 5003 , 2022 2022 Citations: 4
