Artículos (Química Física)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10914

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Theoretical study on the interactions between ibrutinib and gold nanoparticles for being used as drug delivery in the chronic lymphocytic leukemia
(Elsevier, 2020) Sánchez Coronilla, Antonio; Martín Fernández, Elisa Isabel; Fernández de Córdova, Francisco José; Prado Gotor, Rafael; Hidalgo Toledo, José; Química Física; Ingeniería Química; Junta de Andalucía; Universidad de Sevilla; FQM106: Carbolinas
A theoretical study of the interaction of ibrutinib with both cysteine/methyl-cysteine and gold surface is presented. The interest of ibrutinib is that binds through its acrylamide group with the S atom from Cys481 residue of Bruton-tyrosine-kinase (BTK) protein and inhibits the maturation of B-lymphocytes. In a first part, the interaction of ibrutinib through its acrylamide group with cysteine/methyl-cysteine is studied in the range of 298 to 315 K to analyse the effect of increasing the temperature in the binding of the drug with the amine-acid. The interaction is favoured at physiologic temperature but its stability decreases at higher temperatures. Thus, in patients with fever the drug may present a lower effectivity and certain amount of free drug in the blood may appear increasing the risk of toxicity for them. In the second part, the interaction of ibrutinib with a gold surface was studied to explore the possibility of using gold nanoparticles as ibrutinib deliverer. The most stable interaction corresponds to the structure with the nitrogen atoms from pyrimidine moiety and from NH2 directly focused over gold atoms keeping acrylamide group of ibrutinib free for joining to BTK. Therefore, according to the theoretical results gold nanoparticles may be used as ibrutinib deliverer.
Factors that control the gold nanoparticles' aggregation induced by adenine molecules: New insights through a combined experimental and theoretical study
(Elsevier, 2020) Carnerero Panduro, José María; Sánchez Coronilla, Antonio; Jiménez Ruiz, Aila; Prado Gotor, Rafael; Química Física; Ministerio de Economía y Competitividad (MINECO). España; Junta de Andalucía; Universidad de Sevilla
The adsorption of adenine molecules and its derivatives on citrate capped gold nanoparticles (AuNPs) is quantified by a colorimetric method. The strength of the interaction is reflected in the aggregation grade of the colloids, that is detected though the changes in the absorption spectra of the samples, which allow for the determination of apparent binding constants. The positive charge of adenine molecules facilitates the approach to the colloid surface, a fact that is reflected in the measured binding free energies being more negative than those of neutral molecules. In the case of nucleosides and nucleotides, the aggregated structures are smaller or simply do not appear. Theoretical calculations based on density functional theory (DFT) were performed in order to compare the interaction of adenine, adenosine and AMP with gold nanoparticles. Our results indicate the relevance of the N atom of the amino group of adenine, adenosine and AMP in the stabilization with the nanoparticle surface. Thus, in this stabilization the amino group adopts a pyramidal disposition typical of a sp3 hybridization, being found the gold-adenine interaction more stable than that of adenosine and AMP.
Plasmacytoid and cd141+ myeloid dendritic cells cooperation with cd8+ t cells in lymph nodes is associated with hiv control
(Wiley, 2025-09-12) Vitallé, Joana; Bachiller, Sara; Domínguez-Molina, Beatriz; Moysi, Eirini; Ferrando Martínez, Sara; Camacho Sojo, María Inés; Ostos Marcos, Francisco José; Rafii-El-Idrissi Benhnia, Mohammed; López Cortés, Luis Fernando; Ruiz Mateos Carmona, Ezequiel; Medicina; Bioquímica Médica y Biología Molecular e Inmunología; Química Física; FQM206: Grupo de Cinética del Profesor Rodríguez Velasco
Dendritic cells (DC) are known to modulate antiviral immune responses; however, the knowledge about the role of different DC subsets in antiviral T cell priming in human tissues remains uncompleted. In the context of HIV infection, we determined the phenotype and location of plasmacytoid and CD141+ myeloid DCs (pDCs and mDCs) in lymph nodes of people living with HIV (PLWH). We found an interaction between pDCs and CD141+ mDCs with CD8+ T cells, being associated with participants’ viral levels in blood and tissue. Moreover, we demonstrated a higher and more polyfunctional superantigen- and HIV-specific CD8+ T cell response after the coculture with Toll-like receptor (TLR)-primed pDCs and CD141+ mDCs. Last, we showed the potential of programmed cell death-1 (PD-1) blocking using pembrolizumab to further increase antigen-specific CD8+ T cell response along with TLR agonists. Therefore, these results showed a cooperation between pDCs, CD141+ mDCs and CD8+ T cells in lymph nodes of PLWH, which is associated with higher HIV control, highlighting the importance of DC subsets crosstalk to achieve a more potent anti-HIV response and support the use of DC-based immunotherapies for HIV control.
U4+ Speciation in Acidic Aqueous Solution: Insights from UV–Vis, EXAFS, XANES, and Quantum-Statistical Simulations
(ACS, 2025) Raposo Hernández, Gema; Rodríguez Pappalardo, Rafael; Réal, Florent; Vallet, Valérie; Sánchez Marcos, Enrique; Química Física; Agence Nationale de la Recherche. France; University of Lille
This theoretical study investigates the UV–vis absorption properties of U4+-containing aqueous solutions and their relationship with the nature of aqua-complexes present at varying acidic levels. High-level quantum-mechanical calculations─accounting for relativistic effects, spin–orbit coupling, and both dynamic and nondynamic correlation─were combined with classical Molecular Dynamics simulations. EXAFS, XANES, and UV–vis spectra of U4+-containing aqueous solutions were used as experimental reference data and compared with the corresponding theoretical predictions. UV–vis spectra were available at various pH values. Theoretical spectra were generated as averages of individual spectra computed from the structures statistically generated. Coordination numbers ranging from 8 to 10 for the aqua ion were explored. Although the theoretical-experimental comparison of the EXAFS and XANES spectra allows us to reject ten-coordination, assigning the octa- or nine- (ennea-)coordination to the U4+ aqua ion is difficult. However, UV–vis spectroscopy provided some evidence supporting a preference for the ennea-coordination. Spectra for aqueous solutions up to pH 2.22 were compared with simulated spectra of hydrolyzed forms of the aqua ion, in which up to two water molecules were replaced by hydroxyl anions. Spectra obtained as simulated mixtures of the aqua ion and hydrolyzed species in varying ratios produced a spectral evolution with pH that closely resembles experimental observations.
Photoinduced Local Symmetry Breakage in SrTiO3 and Potential Pathways to Ferroelectricity
(ACS, 2025) Rodríguez Remesal, Elena; Posligua Hernández, Víctor Hugo; Plata Ramos, José Javier; Márquez Cruz, Antonio Marcial; Química Física; Red Española de Supercomputación (RES)
During the past few years Strontium Titanate, STO, has been the subject of extensive studies exploring the phase transitions it undergoes from paraelectric to ferroelectric or antiferrodistortive phases, induced by electromagnetic radiation such as lasers. This ability to exhibit photoinduced ferroelectricity has profound implications for its potential applications in photovoltaic and optoelectronic devices. Additionally, SrTiO3 exhibits a rich dielectric behavior under UV irradiation in the presence of an electric field. In this work, we explore the nature of the photoinduced enhancement of the STO dielectric constant under UV irradiation. Analyzing the STO potential energy surface (PES), the first excited states exhibit a local breaking of symmetry due to the displacement of the Ti atom off the center of the unit cell. Furthermore, two key variables linked to the ferroelectric phase transition in STO, namely, pressure and oxygen vacancies, are investigated. Pressure can modify the ground state and excited state PES, tailoring the depth of the excited state well or reducing the energy gap between the ground and excited states. The distribution of oxygen vacancies in the STO bulk was also explored, revealing preferential configurations and the presence of aligned Ti3+-Ovac-Ti3+ or Ti3+-Ovac complexes. These configurations can lead to a small polarization of the material, which could serve as a driving force to align the off-center photoexcited Ti polarons.
Exploring Guanine-cytosine co-adsorption on Gold Electrodes in Basic and Neutral Media: In Situ Insights from Surface-enhanced Infrared Spectroscopy
(Elsevier, 2025) Álvarez Malmagro, Julia; Rueda Rueda, Manuela; Prieto Dapena, Francisco; Química Física; Universidad de Sevilla; Ministerio de Ciencia e Innovación (MICIN). España
In situ Surface-Enhanced Infrared Absorption Spectroscopy in the Attenuated Total Reflection mode (ATR-SEIRAS) has been used to investigate the co-adsorption of guanine (G) and cytosine (C) on gold thin nanostructured gold electrodes at pD 8.0 and 11.6, employing D2O as a solvent. At pD 8.0, at which both bases are in neutral form, the comparison between the ATR-SEIRA bands when guanine (G) and cytosine (C) are co-adsorbed and the corresponding bands of each base adsorbed individually has revealed the existence of T-shaped pi interactions between the two nucleobases, with guanine almost normal to the electrode surface and cytosine parallel. The Watson-Crick or Hoogsteen hydrogen bond interactions, involving the carbonyls groups of the two nucleobase molecules, do not seem to be relevant. In addition, the co-adsorption of guanine maintains the same proportion of adsorbed cytosine tautomers and its evolution with potential than observed in the absence of guanine. At pD 11.6, at which guanine is deprotonated, the experimental results do not show T-shaped pi interaction between the complementary bases, as was proposed at pH 8, and only the competitive adsorption of both bases that originate a decrease in the ATR-SEIRAS band of each adsorbed base when the complementary one is also adsorbed.
Nanotecnología inspirada en la naturaleza: celdas solares sensibilizadas con colorante
(Universidad de Málaga, 2015) Sánchez de Armas, María Rocío; Gutiérrez Beltrán, Emilio; Química Física
Entre los retos más importantes a los que la humanidad debe enfrentarse en la actualidad se encuentranel incremento constante de la demanda de energía y el control de los niveles deCO2(generado por lacombustión de combustibles fósiles) en la atmósfera. Con el fin de solventar estos problemas e inspiradospor el proceso natural de la fotosíntesis los científicos trabajan para transformar de manera eficiente laenergía solar en energía eléctrica, desarrollando y optimizando dispositivos llamados celdas solares. Pese asu gran potencial, la tecnología solar presenta en la actualidad una baja eficiencia, manteniendo abierto unamplio campo de investigación centrado en la optimización de dichos dispositivos. En este artículo se realizauna breve descripción del diseño y el funcionamiento de uno de los tipos de celda solar más prometedores,las celdas solares sensibilizadas con colorante (DSSC).
Thermally-induced Covalent Coupling of Cobalt Porphyrin Molecules on Au(111)
(IOP Publishing, 2025) Bouatou, M.; Montenegro-Pohlhammer, Nicolás; Sánchez de Armas, María Rocío; Barthel, C.; Jiménez Calzado, Carmen; Gruber, M.; Química Física; Deutsche Forschungsgemeinschaft / German Research Foundation (DFG); Ministerio de Ciencia, Innovación y Universidades (MICIU). España
We investigated the thermally induced covalent coupling of cobalt porphyrin (CoP) molecules on an Au(111) surface using scanning tunnelling microscopy and first-principle calculations. While CoP molecules deposited at room temperature remain isolated due to electrostatic repulsion, annealing the substrate leads to their aggregation into chain-like structures with covalent bonding. Three distinct bonding motifs are identified, with calculations revealing weak magnetic coupling between the S = 1/2 Co ions. This work evidences a straightforward method for synthesising multinuclear complexes with magnetically coupled spins on surfaces, offering potential applications in molecular spintronics.
The Second Life of Cobalt MOF: Alternating Magnetic Field‐ Assisted Electrocatalytic Oxygen Evolution Reaction in MOF‐derived Nanoparticles
(Wiley, 2025-06-20) Río Rodríguez, José Luis del; Gutiérrez Tarriño, Silvia; Márquez Escudero, Inmaculada; Gallo Córdova, Álvaro; Molina, M. Asunción; Martínez, Jordan Santiago; Calvente Pacheco, Juan José; Cerezo Navarrete, Christian; Beale, Andrew M.; Morales, María del Puerto; Olloqui Sariego, José Luis; Oña Burgos, Pascual; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Generalitat Valenciana; European Union (UE)
A major challenge in hydrogen production from water electrolysis is the slow kinetics of oxygen evolution (OER). Applying an alternating magnetic field (AMF) to ferromagnetic metal nanoparticles on electrodes has gained attention due to the generation of a thermally activated electrocatalyst, which can boost OER performance. This work studies the influence of external parameters and intrinsic characteristics of carbon-encapsulated cobalt MOF-derived nanoparticles deposited onto graphite paper electrodes on the electrocatalytic AMF-OER coupled process. Specifically, the impact of AMF strength, the electrolyte composition (concentration and cation nature) and cobalt content on the electrocatalytic AMF-OER performance are thoroughly investigated. Results reveal that AMF significantly boosts OER activity of Co@C-based electrodes, their enhancement being strongly dependent on the electrolyte composition. Furthermore, both the heating capacity of the herein synthesized catalyst for magnetic hyperthermia and their structural features remain intact after an intense and prolonged electrocatalytic AMF-OER experiment. No signs of sintering, leaching, or particle size increase, which are typical issues observed when metal nanoparticles are subjected to an intense external magnetic field, have been found. This underscores the high operational stability of this catalyst. These findings provide new insights into thermal AMF-assisted alkaline water oxidation for developing high-performance catalysts for enhanced electrocatalysis.
Effect of Electrostatic Immobilization on the Electrochemistry of Human and Horse Cytochrome c
(Elsevier, 2025) Olloqui Sariego, José Luis; Márquez Escudero, Inmaculada; Guerra Castellano, Alejandra; Molero Casado, Miguel; Rosa Acosta, Miguel Ángel de la; Calvente Pacheco, Juan José; Díaz Moreno, Irene; Andreu Fondacabe, Rafael Jesús; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
Protein film voltammetry is a sensitive tool to characterize the electron transfer properties of redox proteins in a variety of environments and conformational states. Here, a detailed voltammetric study aimed to explore the effect of electrostatic immobilization on the electron transfer thermodynamics and kinetics of adsorbed human- and horse- cytochrome c was carried out. For this purpose, the two cytochromes were adsorbed on thiol monolayers (SAM) with different immobilization strengths and donor–acceptor distances. While thermodynamic redox parameters do not seem to be affected by the monolayer thickness and charge density, electron transfer kinetics are significantly modulated by the protein immobilization strength. Stronger protein–SAM electrostatic interactions result in lower electron transfer rates in both non-adiabatic and friction kinetic regimes. This behavior is further characterized by smaller pre-exponential factors and activation enthalpies in Arrhenius type plots. These kinetic results in the physiologically relevant non-adiabatic electron transfer regime are shown to be consistent with the recently developed Matyushov's theoretical formulation of protein electron transfer. Moreover, a comparison between the kinetic parameters of the two cytochrome variants supports the hypothesis that differences between their electron transfer rates originate in their structural flexibility to accommodate the conformational changes required to form the precursor complex between cytochrome and a negatively charged redox partner.
Switching between Positive and Negative Movement Near an Air/water Interface through Lateral Laser Illumination
(American Institute of Physics, 2020) Shono, M.; Takatori, S.; Carnerero Panduro, José María; Yoshikawa, K.; Química Física; Sociedad Japonesa para la Promoción de la Ciencia (JSPS). Japón
The directional movement of an aqueous solution containing gold nanoparticles under laser irradiation (532 nm) through the vicinity of an air/water interface is reported. It is shown that unidirectional flow is generated along the path of light-travel when a laser is irradiated parallel to the interface. On the contrary, liquid flow toward the light source is caused when the incident angle of the laser is tuned so as to make the total reflection at an air/water interface. Such switching of the flow direction, positive or negative to the light propagation, was applied to the movement of mm-sized floating object, revealing that repetitive back and forth motion of the solid object is generated. This directional switching of photo-induced movement is interpreted by taking into account the flow caused by the spatial gradient of the surface tension due to the thermal effect of the incident laser. A numerical model with a Navier-Stokes-type equation reproduces the essential aspects of the switching of the direction observed in the present study.
Spin-state switching at the single-molecule level by distortion of the coordination sphere: validation based on quantum-chemistry calculations
(Royal Soc Chemistry, 2025-02-03) El Lala, IJ; Montenegro-Pohlhammer, Nicolás; Sánchez de Armas, María Rocío; Jiménez Calzado, Carmen; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE)
Different strategies have been proposed to trigger spin switching in single-molecule junctions based on spin-crossover complexes. Here, we report on a computational study aimed to validate one of the hypothesized mechanisms consisting of the distortion of the coordination sphere of the molecule. We focus on a series of heteroleptic [FeII(tpy)2]+2 complexes in a mechanically controlled break junction setup, displaying voltage-dependent bistabilities, related to the switching of the FeII centre between the LS and HS states. Our model for the molecular junction can explain the hysteretic behaviour found in some of the junctions, with a mechanism close to the hypothesized mechanism, but without the requirement of long-range interactions between the electrodes and different parts of the molecule. Our results predict the existence of a switching field able to foster the required distortion driving the switching between the LS and HS states.
Lead-free hybrid perovskites: Structural and electronic analysis of MA0.5Rb0.5Bi0.5Ge0.25I3 and MA0.5Rb0.5Sb0.5Ge0.25I3
(Elsevier, 2025-04-05) García-Moreno, Fernando; Sánchez Coronilla, Antonio; Martín Fernández, Elisa Isabel; Química Física; Ingeniería Química; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE)
Structural and electronic stability of MA0.5Rb0.5Bi0.5Ge0.25I3 and MA0.5Rb0.5Sb0.5Ge0.25I3 lead-free hybrid perovskites is addressed. The substitution of Pb in MAPbI3 perovskite is increasing the scientific attention due to its toxicity as well as stability of interest in the design of environmentally friendly solar cells. MA cation (CH3NH3 +) is replaced by 50 % Rb+ to improve stability and retain the organic characteristics. The substitution of lead in MA0.5Rb0.5PbI3 structure has been studied up to 100 % Ge. Electron localization function (ELF) analysis for structures with 75 and 100 % of Ge, show zones with no electron localization that indicates certain degree of structural instability. ELF and density of states (DOS) analysis of the structure MA0.5Rb0.5Pb0.5Ge0.5I3 with 50 % Ge corroborate stability characteristics of this perovskite. Thus, the MA0.5Rb0.5Pb0.5Ge0.5I3 structure has been selected for the substitution of lead by Bi and Sb. ELF and non-covalent index (NCI) analysis indicate Sb structures are slightly more stable than those with Bi. The presence of Bi and Sb drastically decreases the bandgap in the MA0.5Rb0.5Bi0.5Ge0.25I3 and MA0.5Rb0.5Sb0.5Ge0.25I3 structures, respectively, which makes both structures without lead of interest for use in photovoltaic devices. These findings provide a pathway for designing stable, lead-free perovskites with improved optoelectronic properties for next-generation solar cells.
Development of a Reliable Device for ‘Fluorokinetic’ Analysis Based on a Portable Diode Array MEMS Fluorimeter
(Multidisciplinary Digital Publishing Institute (MDPI), 2025-04-03) González Arjona, Domingo; López Pérez, Germán; Química Física; Junta de Andalucía; Ministerio de Ciencia e Innovación (MICIN). España
A device was developed to study the evolution of fluorescence spectra as a function of time. A previously designed fluorimeter based on the diode array mini-spectrometer CM12880MA was used. The control and measurement were carried out by programming a SAM21D microcontroller. Considerations regarding the optimization of acquisition speed, memory, and computer interface have been analyzed and optimized. As a result, a very versatile device with great adaptability, reduced dimensions, portability, and a low budget (under EUR 500) has been built. The sensitivity, controlled by the integration time of the photodiodes, can be adjusted between 10 µs and 20 s, thus allowing sampling times ranging from 10 ms to more than 10 h. Under these conditions, chemical rate constants from 20 s−1 to 10−8 s−1 can be experimentally determined. It has a very wide operating range for the kinetic rate constant determination, over six orders of magnitude. As proof of the system performance, the oxidation reaction of Thiamine in a basic medium to form fluorescent Thiochrome has been employed. The evolution of the emission spectrum has been followed, and the decomposition rate constant has been measured at 2.1 × 10−3 s−1, a value which matches those values reported in the literature for this system. A Thiochrome calibration curve has also been performed, obtaining a detection limit of 13 nM, consistent with literature data. Additionally, the stability of Thiochrome has been tested, being the photo-decomposition rate constants 1.8 × 10−4 s−1 and 3.0 × 10−7 s−1, in the presence and absence of UV light (365 nm), respectively. Finally, experiments have been designed to obtain, in a single measurement, the values of both rate constants: the formation of Thiochrome from Thiamine and its photo-decomposition under UV light to a non-fluorescent product. The rate constant values obtained are in good agreement with those previously obtained through independent experiments under the same experimental conditions. These results show that, under these conditions, Thiochrome can be considered an unstable intermediate in a chemical reaction with successive stages.
The two yeast cytochrome c isoforms differentially regulate supercomplex assembly and mitochondrial electron flow
(Elsevier, 2025-06) Guerra Castellano, Alejandra; Aneas, Manuel; Tamargo Azpilicueta, Joaquín; Márquez Escudero, Inmaculada; Olloqui Sariego, José Luis; Calvente Pacheco, Juan José; Rosa Acosta, Miguel Ángel de la; Díaz Moreno, Irene; Bioquímica Vegetal y Biología Molecular; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Junta de Andalucía
Mitochondria play a crucial role in cellular energy production, signaling and homeostasis. Respiratory supercomplexes represent evolutionary well-conserved, stable associations between membrane complexes and molecules, including proteins and lipids, within the inner mitochondrial membrane. They dynamically respond to metabolic demands and enhance the electron transfer rate, thereby reducing the production of ROS. Recent research has unveiled cytochrome c, a mobile electron carrier between complexes III and IV, as a potential key player in orchestrating the formation of these supra-associations. This study centers on elucidating the role of cytochrome c in modulating the assembly of supercomplexes, using the Saccharomyces cerevisiae yeast as a model system for mitochondrial metabolism. BN-PAGE and mass spectrometry-based proteomic analysis were employed to examine supercomplex organization in yeast strains expressing different cytochrome c isoforms, grown under fermentative and respiratory conditions. Our results demonstrate that both isoforms of cytochrome c contribute to supercomplex assembly, with isoform-2 significantly improving electron transfer and lowering ROS levels. We propose a model in which cytochrome c acts as a scaffold for the recruitment of assembly factors, facilitating the formation of higher order supercomplexes such as III2IV2. This model highlights cytochrome c's role beyond electron transfer, as it regulates supercomplex assembly and mitochondrial homeostasis.
Thermodynamics of Solids Including Anharmonicity through Quasiparticle Theory
(Nature, 2024) Blancas, Ernesto J.; Lobato, Álvaro; Izquierdo Ruiz, Fernando; Márquez Cruz, Antonio Marcial; Recio, J. Manuel; Nath, Pinku; Plata Ramos, José Javier; Otero de la Roza, Alberto; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Principado de Asturias; Red Española de Supercomputación (RES)
The quasiharmonic approximation (QHA) in combination with density-functional theory is the main computational method used to calculate thermodynamic properties under arbitrary temperature and pressure conditions. QHA can predict thermodynamic phase diagrams, elastic properties and temperature- and pressure-dependent equilibrium geometries, all of which are important in various fields of knowledge. The main drawbacks of QHA are that it makes spurious predictions for the volume and other properties in the high temperature limit due to its approximate treatment of anharmonicity, and that it is unable to model dynamically stabilized structures. In this work, we propose an extension to QHA that fixes these problems. Our approach is based on four ingredients: (i) the calculation of the n-th order force constants using randomly displaced configurations and regularized regression, (ii) the calculation of temperature-dependent effective harmonic frequencies ω(V, T) within the self-consistent harmonic approximation (SCHA), (iii) Allen’s quasiparticle (QP) theory, which allows the calculation of the anharmonic entropy from the effective frequencies, and (iv) a simple Debye-like numerical model that enables the calculation of all other thermodynamic properties from the QP entropies. The proposed method is conceptually simple, with a computational complexity similar to QHA but requiring more supercell calculations. It allows incorporating anharmonic effects to any order. The predictions of the new method coincide with QHA in the low-temperature limit and eliminate the QHA blowout at high temperature, recovering the experimentally observed behavior of all thermodynamic properties tested. The performance of the new method is demonstrated by calculating the thermodynamic properties of geologically relevant minerals MgO and CaO. In addition, using cubic SrTiO3 as an example, we show that, unlike QHA, our method can also predict thermodynamic properties of dynamically stabilized phases. We expect this new method to be an important tool in geochemistry and materials discovery.
Enhancing the Thermoelectric Figure of Merit of BiN Via Polymorphism, Pressure, and Nanostructuring
(Royal Society of Chemistry, 2024) Rodríguez Remesal, Elena; Posligua Hernández, Víctor Hugo; Mahíllo Paniagua, M.; Glazyrin, K.; Fernández Sanz, Javier; Márquez Cruz, Antonio Marcial; Plata Ramos, José Javier; Química Física; Ministerio de Ciencia e Innovación (MICIN). España; Red Española de Supercomputación (RES)
Materials discovery extends beyond the synthesis of new compounds. Detailed characterization is essential to understand the potential applications of novel materials. However, experimental characterization can be challenging due to the vast chemical and physical spaces, as well as the specific conditions required for certain techniques. Computational high-throughput methods can overcome these challenges. In this work, the transport and thermoelectric properties of the recently synthesized bulk BiN are explored, including the effects of temperature, pressure, carrier concentration, polymorphism and polycrystalline grain size. We find that the band structure is strongly dependent on pressure and the polymorph studied. Both polymorphs exhibit low thermal conductivity at 0 GPa, which rapidly increases when pressure is applied. Electronic transport properties can be finely tuned based on the effects of pressure and polymorph type on the band gap, carrier mobilities, and presence of secondary pockets. The thermoelectric figure of merit can reach values around 0.85 for both p- and n-type BiN if the power factor and lattice thermal conductivity are optimized at 600 K, making this material competitive with other well-known thermoelectric families, such as Bi2Te3 or PbX, in the low-to-medium temperature range.
Challenges Reconciling Theory and Experiments in the Prediction of Lattice Thermal Conductivity: The Case of Cu-Based Sulvanites
(American Chemical Society, 2024) Caro Campos, I.; González Barrios, M. M.; Dura, O. J.; Fransson, E.; Plata Ramos, José Javier; Ávila, D.; Fernández Sanz, Javier; Prado Gonjal, J.; Márquez Cruz, Antonio Marcial; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Comunidad Autónoma de Madrid; Red Española de Supercomputación (RES)
The exploration of large chemical spaces in search of new thermoelectric materials requires the integration of experiments, theory, simulations, and data science. The development of high-throughput strategies that combine DFT calculations with machine learning has emerged as a powerful approach to discovering new materials. However, experimental validation is crucial to confirm the accuracy of these workflows. This validation becomes especially important in understanding the transport properties that govern the thermoelectric performance of materials since they are highly influenced by synthetic, processing, and operating conditions. In this work, we explore the thermal conductivity of Cu-based sulvanites by using a combination of theoretical and experimental methods. Previous discrepancies and significant variations in reported data for Cu3VS4 and Cu3VSe4 are explained using the Boltzmann Transport Equation for phonons and by synthesizing well-characterized defect-free samples. The use of machine learning approaches for extracting high-order force constants opens doors to charting the lattice thermal conductivity across the entire Cu-based sulvanite family─finding not only materials with κl values below 2 W m-1 K-1 at moderate temperatures but also rationalizing their thermal transport properties based on chemical composition.
Selective Design of MOF-derived Electrocatalytic Interphases by Potential-driven Surface Reconstruction
(Elsevier, 2025) Hernández Salvador, Sergio; Márquez Escudero, Inmaculada; Gutiérrez Tarriño, Silvia; Calvente Pacheco, Juan José; Río Rodríguez, José Luis del; Oña Burgos, Pascual; Andreu Fondacabe, Rafael Jesús; Olloqui Sariego, José Luis; Química Física; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Junta de Andalucía; Ministerio de Ciencia e Innovación (MICIN). España; Generalitat Valenciana; Universitat Politècnica de València (UPV)
Metal-organic frameworks (MOFs) can be used as precursors for the directed synthesis of derived materials with enhanced performance for electrocatalysis. Herein, we report on an in-situ electrochemical strategy for the selective synthesis of hybrid electrocatalysts using a cobalt MOF (2D-CoMOF) as a precursor for constructing electrochemical sensors to monitor the glucose oxidation reaction (GOR). By using in-situ Raman spectroelectrochemistry, it is demonstrated that a precise control of the applied potential during amperometric treatment of 2D-CoMOF can promote the generation of derived heterostructures in which the original MOF coexists with metal oxides and/or oxyhydroxides (MOF-MOx) with different compositions. The so-prepared electrodes exhibit high electroactive surface areas, a high number of electrocatalytically active cobalt sites and an efficient charge transport across the catalytic film. Moreover, their composition-dependent electrocatalytic performance for the glucose oxidation reaction is examined, establishing a relationship between the applied potential, the macroscopic chemical composition of the heterostructure and the electrocatalytic performance for glucose sensing. In particular, the hybrid phases consisting of Co-MOF/Co3O4/CoOOH display superior electrocatalytic sensing performance with a wide linear concentration range and high sensitivity. The present work emphasizes the significance that the precise control of the applied potential has on the electrochemically-assisted MOF transformation for developing highly efficient MOF-derived electrocatalysts.
Influence of carbon nanotubes on the antimicrobial character of the β-lactam antibiotics Cefepime and Meropenem
(Elsevier, 2025-05) Bernal Pérez, Eva; Mata Hijosa, Laura; López-Cornejo, María del Pilar; Moyá Morán, María Luisa; Madinabeitia, Nuria; Merino Bohórquez, Vicente; López-López, Manuel; Lebrón Romero, José Antonio; Química Física; Farmacología
The overuse of antibiotics over decades has led to a multi-resistance of bacteria that today poses a serious threat to human health. β-lactam antibiotics are one of the most prescribed drugs against bacterial infectious diseases, which has conducted to increased resistance. The short half-life of these drugs results in low bioavailability, which limits their clinical use and requires continuous administration by infusion. Encapsulation of these antibiotics in nanocarriers would improve their biopharmaceutical properties by protecting them. With this in mind, single- and multi-walled carbon nanotubes (SWCNTs and MWCNTs, respectively) were used here as nanocarriers for the antibiotics Meropenem and Cefepime. The adsorption process of these antibiotics in the carbon nanotubes (CNTs) was optimized to obtain a high encapsulation efficiency. The complexes CNT/drug prepared were characterized by dynamic light scattering and spectroscopic measurements. The growth of Escherichia coli and Staphylococcus aureus bacteria was analyzed in the presence of the CNT/drug complexes to evaluate the pharmacological properties of the encapsulated antibiotics. Results showed lower minimum inhibitory concentration (MIC) values of the CNT/drug complexes compared to free drugs. This indicates the preservation of the pharmacological properties of the encapsulated antibiotics. In addition, the stability of the encapsulated antibiotics was observed to last at least 24 h, which was a great improvement compared to the free drugs.

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