A5070186305- Gold and Silver Nanoparticles Synthesis and Applications
- Spectroscopy and Quantum Chemical Studies
- Electrochemical Analysis and Applications
- Advanced Chemical Physics Studies
- Molecular spectroscopy and chirality
- Molecular Spectroscopy and Structure
- Molecular Junctions and Nanostructures
- Nanocluster Synthesis and Applications
- Protein Interaction Studies and Fluorescence Analysis
- Atmospheric Ozone and Climate
- Spectroscopy Techniques in Biomedical and Chemical Research
- Chemical Reactions and Mechanisms
- Analytical Chemistry and Chromatography
- Atmospheric chemistry and aerosols
- Nonlinear Optical Materials Research
- Photochemistry and Electron Transfer Studies
- Free Radicals and Antioxidants
- Synthesis and Biological Evaluation
- Quantum Dots Synthesis And Properties
- Advanced biosensing and bioanalysis techniques
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Spectroscopy and Chemometric Analyses
- Advanced Chemical Sensor Technologies
- Crystallography and molecular interactions
Universidad de Málaga
2016-2025
Technological Corporation of Andalusia
2014-2021
Hospital Universitario de Santander
2009-2019
Consejo Superior de Investigaciones Científicas
2019
Industrial University of Santander
2019
Instituto de Estructura de la Materia
2007-2019
Comisión Sectorial de Investigación Científica
2014-2018
Centro Médico Sanitas Málaga
2014
Texas Tech University
2005-2009
National Institute for Materials Science
2009
This work reports the formation of both solid and hollow lignin micro- nanofibers, at room temperature without polymer binders, by co-electrospinning. These fibers, after thermal stabilization, are carbonized to produce carbon nanofibers (see figure) with specific surface areas similar values found for active carbon.
The surface-enhanced Raman scattering (SERS) spectra of pyridine have been analyzed on the basis a resonant charge transfer (CT) mechanism. most intense bands recorded in SERS at negative electrode potentials correspond with normal modes that connect equilibrium geometries neutral molecule and corresponding radical anion. These characterized according to our previously proposed method by calculating ab initio its anion then building transformation ΔQ = L-1ΔR, where vector contains those...
Surfaced-enhanced Ramon scattering (SERS) spectra of pyrazine are analyzed on the basis properties electronic states metal-adsorbate surface complex. Ab initio CIS calculations have been carried out for Ag2-pyrazine complex, which enabled us to find two excited singlets, namely CT0;1B1 and CT1;1A2, with quite similar those radical anion in its B3u2 Au2 states, respectively, energies falling range exciting photons usually employed Raman spectroscopy. SERS compatible a resonance enhancement...
A new general procedure to interpret surface-enhanced Raman scattering (SERS) spectra has been developed in order clarify the controversy concerning relevant enhancement mechanism of this type spectra. The analysis consists detecting presence charge transfer (CT) by correlating most enhanced SERS bands with ab initio calculated geometries (ΔQ) and vibrational frequencies (Δv) isolated molecule its radical anion. This CT is assumed be identical that resonance between electronic ground state...
SERS spectra of pyrazine on silver electrode have been recorded and analyzed, assuming a charge transfer effect using selection rules analogous to those resonance Raman. With the aim predicting this mechanism selective enhancement fundamentals, method has proposed based an analysis results geometry optimizations carried out by ab initio calculations. The strongest bands coincide with assigned normal modes connecting equilibrium geometries neutral molecule radical anion. These support...
Silver nanoparticles (NPs) functionalized with the molecular assembler bis-acridinium dication lucigenin (LG) have been used as a chemical sensor system to detect group of polycyclic aromatic hydrocarbon (PAH) pollutants in multicomponent mixture by means surface-enhanced raman scattering (SERS). The effectiveness this was checked for PAHs different numbers fused benzene rings, namely anthracene, pyrene, triphenylene, benzo[c]phenanthrene, chrysene, and coronene. In order determine host...
Carbendazim (MBC) is a fungicide widely used in agriculture, and there are serious concerns regarding the health risks that could be caused by this fungicide. Here, we explore its ultrasensitive detection surface‐enhanced Raman scattering (SERS). First, to obtain maximum SERS signal, adsorption of target molecule onto metallic surface essential. Therefore, study MBC nanoparticle under different experimental conditions, such as synthesis methods nanoparticle, variable excitation wavelength,...
This communication reports, for the first time, dependence of SERS intensities under resonant CT conditions (SERS-CT) on electrode potential. SERS-CT have been estimated from properties S0–CTi transitions ranging between 200–1200 nm selected [Agn–pyridine]q and [Agn–pyrazine]q complexes.
Quantum mechanical calculations of the ground and excited electronic states several [Agn–pyridine]q complexes yield a linear dependence energies surface states, especially metal-to-molecule charge transfer on qeff = q/n. This is first theoretical approach to modelling effect electrode potential SERS.
A Surface-Enhanced Raman Scattering (SERS) spectrum of 4-cyanopyridine (4CNPy) was recorded on silver plasmonic nanoparticles and analyzed by using Density Functional Theory (DFT) calculations. Two simple molecular models the metal-4CNPy surface complex with a single cation or neutral dimer (Ag+-4CNPy, Ag2-4CNPy), linked through two possible interacting sites 4CNPy (aromatic nitrogen, N, nitrile group, CN), were considered. The calculated vibrational wavenumbers intensities adsorbate...
Surface-enhanced Raman spectra (SERS) of pyrimidine recorded on a silver electrode have been analyzed the basis resonant (RR) process involving photoexcited charge transfer (CT) states metal−adsorbate surface complex. The main feature SERS benzene and azine derivatives is enhancement totally symmetric ring stretching mode 8a due to Franck−Condon contributions related CT transition. Although this behavior observed in pyrimidine, its spectrum also characterized by strong nontotally 8b. This...
The analysis of photoinduced charge transfer (CT) processes in a particular SERS spectrum is not trivial task since each system must be studied separately and no universal selection rules can proposed for this kind enhancement mechanism. Despite this, we found out previous studies that the SERS-CT spectra benzene-like molecules are mainly characterized by strong totally symmetric 8a ring-stretching vibration have used as propensity rule to recognize presence resonant CT these adsorbates....
The relevant low-lying singlet and triplet potential energy surfaces in the photolysis of nitromethane have been studied by using multistate extension multiconfigurational second-order perturbation theory conjunction with large atomic natural orbital-type basis sets. proposed mechanism for photolytic decomposition CH3NO2 provides a consistent reinterpreted picture available experimental results. Two reaction paths are found after excitation at 193 nm: (1) Major Channel, CH3NO2(1A′)+hν(193...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA Priori Scaled Quantum Mechanical Vibrational Spectra of trans- and cis-StilbeneJuan Francisco Arenas, Isabel Lopez Tocon, Juan Carlos Otero, Ignacio MarcosCite this: J. Phys. Chem. 1995, 99, 29, 11392–11398Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July 1995https://pubs.acs.org/doi/10.1021/j100029a015https://doi.org/10.1021/j100029a015research-articleACS PublicationsRequest reuse...
A general model concerning the role of electrode potential on charge-transfer enhancement mechanism SERS is proposed, justifying existence a parameter β which reduces effectiveness in order to shift excited level. This explains observed deviation from unity, and allows for relating intensity/electrode-potential (SERS−CT) profiles similar adsorbates with respective electron affinities. The pyridine, pyrazine methylpyrazines have been recorded silver, being found that maximum SERS−CT shifts...
Infrared and Raman spectra of [1H4]pyrazine [2H4]pyrazine have been reinvestigated a general assignment all the observed bands is proposed which modifies some previous assignments fundamental vibrations. The present satisfies isotopic product rule for i.r.- Raman-active fundamentals. On this basis thermodynamic functions computed.
The chemical changes associated to the autooxidation process of linoleic acid (LA) were detected by Raman spectroscopy and interpreted in light density functional theory (DFT) calculations performed for both fatty its main oxidation products. present methodology, applied a six‐day period upon induction (through heating), allowed understand modifications occurring during process. was shown be suitable reliable technique assessing degree samples, particularly pure acids, mainly when...
Rohit Chikkaraddy opened the discussion of Introductory Lecture: Regarding quantifying chemical enhancement, you showed a systematic change in SERS enhancement for halide substituted molecules due to charge transfer from metal. Is extra an inherent increas
Photoexcitation of 4-methoxyphenyl azide at 266 nm yields triplet nitrene after decaying through an intersystem crossing (<bold>ISC1</bold>, 2<sup>1</sup>A′/2<sup>3</sup>A′′) in a first step followed by internal conversion (<bold>CI2</bold>, 2<sup>3</sup>A′′/1<sup>3</sup>A′′).