Person:
Cortés Gil, Raquel

Profile Picture
First Name
Raquel
Last Name
Cortés Gil
URI
https://hdl.handle.net/20.500.14352/76155
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Inorgánica
Area
Química Inorgánica
Identifiers
UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet IDGoogle Scholar ID

Filters

20193
Reset filters

Settings

End date: 2019 × Start date: 2019 ×

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Complex structural ordering of the oxygen deficiency in La_-0.5 Ca_2.5Mn_2O_7-delta Ruddlesden-Popper phases
    (Acta crystallographica a-foundation and advances, 2019) González Merchante, Daniel; Cortés Gil, Raquel; Alonso Rodríguez, José María; Matesanz Sáez, Emilio; Rivera Calzada, Alberto Carlos; Santamaría Sánchez-Barriga, Jacobo; Ruiz González, María Luisa; González Calbet, José María
    Ruddlesden-Popper oxides, (AO)(ABO_3))_n, occupy a prominent place in the landscape of materials research because of their intriguing potential applications. Compositional modifications to the cation sublattices, A or B, have been explored in order to achieve enhanced functionalities. However, changes to the anionic sublattice have been much less explored. In this work, new oxygen-deficient manganese Ruddlesden-Popper-related phases, La_0.5Ca_2.5Mn_2O_6.5, and La_0.5Ca_2.5Mn_2O_6.25, have been synthesized by controlled reduction of the fully oxidized n = 2 term La_0.5Ca_2.5Mn_2O_7. A complete structural and compositional characterization, by means of neutron diffraction, electron diffraction and atomically resolved scanning transmission electron microscopy and electron energy-loss spectroscopy techniques, allows the proposition of a topotactic reduction pathway through preferential oxygen removal in the [MnO_2] layers along [031] and [013] directions. The gradual decrease of the Mn oxidation state, accommodated by short-range ordering of anionic vacancies, reasonably explains the breaking of ferromagnetic interactions reinforcing the emergence of antiferromagnetic ones. Additional short-range order-disorder phenomena of La and Ca cations have been detected in the reduced La_0.5Ca_2.5Mn_2º_7-delta, as previously reported in the parent compound.
  • Thumbnail Image
    Item
    Project number: 52
    I.amAble: El aprendizaje en ciencias al servicio de la inclusión educativa
    (2019) Herrero Domínguez, Santiago; Corrales Castellanos, María Eugenia; Sobrino Díaz, María Lourdes; Cilleros Prados, Olga; Barba Fernández, Carmen; Azor Lafarga, Alberto Eduardo; Hernández Díaz, María Yolanda; Martínez Del Pozo, Álvaro; Ranchal Sánchez, Rocío; Maestre Varea, David; Méndez Pozo, Gonzalo Rubén; Gervás Gómez-Navarro, Pablo; Pastor Gil, Lorena; Taravillo Corralo, Mercedes; Guerrero Martínez, Andrés; Sánchez Benítez, Francisco Javier; Martín Conde, María; Priego Bermejo, José Luis; González Prieto, Rodrigo; Jiménez Aparicio, Reyes; Álvarez Serrano, Inmaculada; Cortés Gil, Raquel; Osío Barcina, José De Jesús; Mancheño Real, María José; Arribas Fernández, Paula; Lobato Fernández, Álvaro; Sánchez Arroyo, Antonio José; Torrecilla Manresa, Sofía; Cárdenas Bonett, Marlón Félix; Desvoyes, Benedicte; Bárcena Espelleta, Araceli; Nacenta Torres, Pablo; Rubio Lago, Luis; Bautista Blasco, Susana; Julián Cortés, Alvaro; Arancibia Llaneza, Julieta Noelia; Lombraña Pascual, Rodrigo; Catalán Torrecilla, Cristina; Gutiérrez Franco, Yanna María; Martínez Ruiz, María Paloma
    I.amAble es un proyecto que nació con una filosofía centrada en la utilización de acciones de solidaridad como método de aprendizaje. Se diseñan y organizan talleres científicos inclusivos para realizarlos en parejas formadas por personas con discapacidad cognitiva y de educación secundaria ordinaria. Se pretende aprender a la vez que se da un servicio a la universidad y a la sociedad, y ese es el espíritu que se ha seguido manteniendo durante esta tercera edición del curso 2018-2019.
  • Thumbnail Image
    Item
    Magnon-mediated magnetoresistance in layered manganites
    (Physical review B, 2019) Hernando Grande, Antonio; Cortés Gil, Raquel; González Merchante, Daniel; Hernando González, María; Alonso Rodríguez, José María; García García Tuñón, Miguel Ángel; Martínez, José L.; Ruiz Gonález, María Luisa; González Calbet, José María
    We describe here a type of magnetoresistance that takes place in naturally layered and outstanding ordered single phase manganites that may be mediated by magnon excitation. In particular, we show the effect for the Ruddlesden-Popper compound, LaSr2Mn2O7 synthesized by ceramic method. This material exhibits, besides the conventional colossal magnetoresistance, another type of magnetoresistance at low temperature, associated with breaking of the A-type antiferromagnetic coupling of Mn-containing planes. Excitation of magnons or application of a magnetic field breaks this antiparallel alignment so that some electrons, initially confined on the planes, become itinerant along the interplain directions through a double exchange mechanism, giving rise to resistance variations of the order of similar to 60% for polycrystalline samples. The effect described here might be present in other types of manganites exhibiting a natural layered structure, opening up the possibility of developing magnetoresistive devices based on antiferromagnetic oxide materials without requiring artificial multilayered structures.