Person:
Martínez-Haya, Bruno

Catedrático/a de Universidad
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First Name
Bruno
Last Name
Martínez-Haya
Affiliation
Universidad Pablo de Olavide
Department
Sistemas Físicos, Químicos y Naturales
Research Center
Area
Química Física
Research Group
Física Estadística de Líquidos
PAIDI Areas
Física, Química y Matemáticas
PhD programs
Tecnología Química y de Materiales
Identifiers
UPO investigaORCIDScopus Author IDWeb of Science ResearcherIDDialnet ID

Search Results

Now showing 1 - 3 of 3
  • Publication
    Dynamic Proton Bond: MH+·H2O ⇌ M·H3O+ Interconversion in Loosely Coordinated Environments
    (American Chemical Society, 2023-01-26) Martínez-Haya, Bruno; Avilés-Moreno, Juan Ramon; Gámez, Francisco; Martens, Jonathan; Oomens, Jos; Berden, Giel
    The interaction of organic molecules with oxonium cations within their solvation shell may lead to the emergence of dynamic supramolecular structures with recurrently changing host–guest chemical identity. We illustrate this phenomenon in benchmark proton-bonded complexes of water with polyether macrocyles. Despite the smaller proton affinity of water versus the ether group, water in fact retains the proton in the form of H3O+, with increasing stability as the coordination number increases. Hindrance in many-fold coordination induces dynamic reversible (ether)·H3O+ ⇌ (etherH+)·H2O interconversion. We perform infrared action ion spectroscopy over a broad spectral range to expose the vibrational signatures of the loose proton bonding in these systems. Remarkably, characteristic bands for the two limiting proton bonding configurations are observed in the experimental vibrational spectra, superimposed onto diffuse bands associated with proton delocalization. These features cannot be described by static equilibrium structures but are accurately modeled within the framework of ab initio molecular dynamics.
  • Publication
    High-resolution mass spectrometry identification of dye compounds and their degradation products in American cochineal from a historic shipping cargo
    (Elsevier, 2023-04-10) Martínez-Haya, Bruno; López Gámez, José; Rodríguez Hortal, Ana; Domínguez Castillo, Carmen
    Cochineal dyes constitute paradigmatic organic compounds that guide in the elucidation of historic cultural and economical exchanges. This study combines liquid chromatography and high-resolution tandem mass spectrometry to assess the degradation products of the organic dyes of American cochineal collected from the cargo of a 16th century sunken wreck. The identification of biological materials of historical and archeological origin is often challenging due to molecular degradation. In this scenario, the mapping of the chemical routes underlying the fate of the organic and biochemical compounds employed as taxonomic biomarkers becomes of crucial importance. This work shows that, under harsh environmental conditions, the original carminic and (flavo) kermesic acid structures of cochineal dyes are prone to chemical transformation, typically losing the carboxylic acid and glucoside groups. The anthraquinone core is preserved in the majority of degradation products identified in this study, with eventual side chains reminiscent of a partial degradation of the glucoside moiety. The comparison of these observations with the analysis of modern cochineal samples allows us to lay out an updated chart of dye compounds and degradation products which should constitute a seminal benchmark for future biomolecular analysis of historic and archeological dye materials.
  • Publication
    Molecular Characterization of Nonvolatile Fractions of Algerian Petroleum with High-Resolution Mass Spectrometry
    (American Chemical Society, 2021-05-06) Saad, Fatima; Bounaceur, Boumedienne; Daaou, Mortada; Avilés-Moreno, Juan Ramon; Martínez-Haya, Bruno
    Algerian crude oil displays a marked propensity for asphaltene precipitation, leading to solid deposits during extraction, transportation, and storage. The relationship between precipitation and chemical composition is unclear; in fact, Algerian crude oil actually features a low asphaltene concentration, despite its relatively large rate of deposit formation. The rationalization of the precipitation process and its remediation should benefit from a molecular characterization of the crude oil. In this study, two unstable asphaltene fractions (A1 and A2) from two different deposits, and two resin crude oil fractions (R1 and R2) from the Hassi-Messaoud Algerian field have been characterized at the molecular level by means of high-resolution mass spectrometry with an Atmospheric Pressure Chemical Ionization (APCI) source. Positively and negatively charged compounds with molecular weights 200−1200 m/z were detected. Several thousand molecular stoichiometries were identified and classified for each sample, in terms of heteroatom content and aromaticity, searching for trends characteristic of the two asphaltenes and of the associated resins. The A2 asphaltene, from a downstream storage tank, displays a higher aromaticity and O heteroatom content, which correlates with an enhanced aggregation propensity, in comparison to the A1 fraction, collected at the well bore. The resin fractions are found to be abundant in aliphatic hydrocarbons and heteroatomic compounds of moderate aromaticity. The more polar resin fraction, R2, is enriched in N-containing species, with respect to the less polar resin fraction R1, which correlates with the stabilizing function observed in previous works. The results stress the view of crude oil fractions as complex mixtures, rather than in terms of average prototypical compounds, when facing the understanding of asphaltene deposition conditions.