Graphic summary
  • Show / hide key
  • Information


Scientific and technological production
  •  

1 to 50 of 98 results
  • The structure of molten AgCl, AgI and their eutectic mixture as studied by molecular dynamics simulations of polarizable ion model potentials

     Alcaraz Sendra, Olga; Bitrian Varea, Vicente; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 134, p. 014505-014505-9
    DOI: 10.1063/1.3506867
    Date of publication: 2011-01-05
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Molecular dynamics of polarizable point dipole models for molten NaI. Comparison with first principles simulations

     Bitrian Varea, Vicente; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    EPJ Web of Conferences
    Vol. 15, p. 1-3
    DOI: 10.1051/epjconf/20111502009
    Date of publication: 2011-05-18
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Access to the full text
    A polarizable ion model for the structure of molten CuI  Open access

     Bitrian Varea, Vicente; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 134, num. 4, p. 044501-1-044501-6
    DOI: 10.1063/1.3525461
    Date of publication: 2011-01-24
    Journal article

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    The results are reported of the molecular dynamics simulations of the coherent static structure factor of molten CuI at 938 K using a polarizable ion model. This model is based on a rigid ion potential to which the many body interactions due to the anions induced polarization are added. The calculated structure factor reproduces the clear sharp prepeak observed in neutron diffraction data. The corresponding partial structure factors and the related radial distribution functions calculated by molecular dynamics are compared with those found in the literature derived from a combination of neutron and x-ray diffraction data with the aid of the reverse Monte Carlo simulation technique, as well as those calculated by ab initio MD simulations.

  • Estudio de modelos de ión polarizables para sales fundidas mediante dinámica molecular  Open access

     Bitrian Varea, Vicente
    Department of Applied Physics, Universitat Politècnica de Catalunya
    Theses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    La presente tesis es un estudio mediante simulaciones de dinámica molecular de los efectos de la polarización inducida en las propiedades de las sales fundidas, en concreto de los haluros de plata. Estas sales se caracterizan por exhibir en estado sólido conductividades iónicas excepcionalmente altas, comparables a las de los haluros alcalinos en fase líquida, lo que se conoce como comportamiento superiónico. Las aplicaciones tecnológicas de las sales superiónicas abarcan ámbitos diversos, como las baterías recargables de litio ligeras, las pilas de combustible o los sensores de gas. Los modelos utilizados para reproducir el comportamiento de las sales fundidas pueden clasificarse en dos categorías, modelos de ión polarizable (PIM) o de ión rígido (RIM), según si incluyen o no los momentos dipolares inducidos en los iones. Si en los PIM se asume que los momentos dipolares son debidos únicamente al campo eléctrico creado por los demás iones, en determinadas circunstancias puede producirse la polarización catastrófica, que consiste en un crecimiento incontrolado de los momentos dipolares iónicos. Las causas de esta anomalía y las circunstancias en que tiene lugar han sido analizadas teóricamente, y para evitarla se ha propuesto un nuevo tipo de PIM en los que a la polarización inducida por el campo eléctrico se añade la debida a la deformación de las capas electrónicas de los iones como consecuencia de su solapamiento con las de los vecinos más próximos. La influencia de la polarización en la estructura y el transporte iónico de AgBr y AgI fundidos se ha valorado comparando los resultados obtenidos con RIM y diversos PIM. Las propiedades simuladas con PIM en los que se tiene en cuenta la polarizabilidad de los aniones muestran un mejor acuerdo con los resultados experimentales, lo que permite concluir que la polarización juega un papel importante en estas sales. En particular, se consiguen reproducir los rasgos más característicos de los factores de estructura coherente estáticos obtenidos mediante la difracción de neutrones, como el triple rizado del pico principal de AgBr o el prepico de AgI. Las simulaciones permiten demostrar además que dicho prepico señala la existencia de una ordenación de medio alcance propiciada por la creación de zonas de baja densidad de cationes (o voids) como consecuencia de la inducción de polarización. Se ha deducido el teorema de fluctuación-disipación para la función de respuesta dieléctrica en PIM, que revela que la respuesta de una sal a un campo eléctrico externo débil depende de las correlaciones en el equilibrio entre momentos dipolares. El comportamiento de las propiedades dieléctricas de AgI y NaI fundidos muestra diferencias importantes en función de si se incluyen o no los efectos de la polarización. Además se han llevado a cabo simulaciones de AgI en estado sólido, que permiten reproducir el comportamiento superiónico de la fase -AgI, y se ha comenzado a estudiar de forma preliminar la estructura de CuI fundido, obteniendo de nuevo una mejora sustancial al tener en cuenta la polarización inducida en los iones de iodo.

    The present PhD Thesis is a molecular dynamics (MD) study of the effects of induced polarization on the properties of molten salts, in particular silver halides. These salts are notable for exhibiting exceptionally high values of ionic conductivity in solid phase, comparable to those of molten alkali halides. Such a behaviour is known as superionic. The technological applications of superionic salts are widespread, ranging from lightweight high-power-density lithium-ion batteries to fuel cells or gas sensors. The models used to reproduce the molten salts behaviour can be classified into two categories: polarizable ion models (PIM) or rigid ion models (RIM), depending on whether they include or not the dipole moments induced on the ions. The PIM in which it is assumed that dipole moments are only caused by the electric field created by other ions can yield, in certain situations, to an unphysical growth of ionic dipoles, known as polarization catastrophe. The causes of this anomaly, and the circumstances in which it takes place, have been studied analytically, and a new type of PIM has been suggested to solve it. In these new models, a contribution to the polarization is added to that induced by the electric field, due to the deformation of the electronic shells of the ions as a consequence of their overlap with nearest-neighbour shells. The influence of polarization on the structure and ionic transport of molten silver bromide (AgBr) and iodide (AgI) has been assessed by comparing the results obtained with RIM and several different PIM. The properties simulated with PIM in which anion polarizability is allowed for show an improved agreement with experimental results. This fact allows us to conclude that polarization plays a major role in these salts. In particular it is possible to reproduce the main features of the coherent static structure factors obtained experimentally by neutron diffraction, like the three-peak feature characteristic of AgBr or the prepeak in AgI. Furthermore, MD simulations are useful to suggest that this prepeak signals the existence of a medium-range order in the salt structure, related to the opening of low-density cationic regions (or voids) as a result of induced polarization. The fluctuation-dissipation theorem for the dielectric response function in PIM has been theoretically derived. It proves that the molten salt response to the application of a weak external electric field depends on the equilibrium correlations of charge- and dipole moment-density. Molten AgI and NaI dielectric properties show important differences if polarization effects are included or not in the model. Simulations of silver iodide in solid state have been also performed, that succeed in reproducing the superionic behaviour of -AgI phase. In addition, a preliminary study of the structure of molten CuI has been made that concludes that substantial improvement is obtained provided that polarization induced on iodide ions is considered in the description.

  • Molecular dynamics study of polarizable ion models for molten copper halides

     Alcaraz Sendra, Olga; Bitrian Varea, Vicente; Trullàs Simó, Joaquim
    Congreso de Física Estadística
    p. 60
    Presentation's date: 2011-06-02
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • The longitudinal optic-like mode in molten alkali halides: A molecular dynamics approximation to inelastic x-ray scattering experiments

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 132, num. 054503, p. 1-10
    DOI: 10.1063/1.3298863
    Date of publication: 2010-02-07
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • PROPIEDADES DINAMICAS EN FASES LIQUIDAS: SALES FUNDIDAS, DISOLUCIONES IONICAS Y LIQUIDOS MOLECULARES

     Sese Castel, Gemma; Rey Oriol, Rosendo; Trullàs Simó, Joaquim; Ortiz de Urbina Viade, Jordi; Canales Gabriel, Manel; Marti Rabassa, Jordi; Bitrian Varea, Vicente; Calvo Minguillon, Ausias March; Sala2 Viñas, Jonàs; Guardia Manuel, Elvira
    Competitive project

     Share

  • Molecular dynamics of polarizable point dipole models for molten NaI. Comparison with first principles simulations"

     Bitrian Varea, Vicente; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Fourteenth International Conference on 'Liquid and Amorphous Metals'
    p. 113
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • GRUP DE SIMULACIO PER ORDINADOR EN MATERIA CONDENSADA

     Pastor Satorras, Romualdo; Sese Castel, Gemma; Rey Oriol, Rosendo; Casulleras Ambros, Joaquin; Trullàs Simó, Joaquim; Bitrian Varea, Vicente; Baronchelli, Andrea; Osychenco, Oleg; Canales Gabriel, Manel; Boronat Medico, Jordi; Marti Rabassa, Jordi; Macia Rey, Adrian; Calvo Minguillon, Ausias March; Ortiz de Urbina Viade, Jordi; Mazzanti Castrillejo, Fernando Pablo; Astrakharchik, Grigori; Rota, Riccardo; Sala2 Viñas, Jonàs; Guardia Manuel, Elvira
    Competitive project

     Share

  • Static dielectric properties of polarizable ion models: Molecular dynamics study of molten AgI and NaI

     Bitrian Varea, Vicente; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 130, p. 234504-1-234504-10
    DOI: 10.1063/1.3152241
    Date of publication: 2009-06
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • The Static Dielectric Function for Polarizable Ion Models. Molecular Dynamics Study of Molten AgI and NaI

     Bitrian Varea, Vicente; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    7th Liquid Matter Conference
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Molecular dynamics study of the structure of molten mixture Ag(Cl0.43I0.57)

     Bitrian Varea, Vicente; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    7th Liquid Matter Conference
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Molecular Dynamics Study of Polarization Effects on AgI

     Trullàs Simó, Joaquim; Bitrian Varea, Vicente
    Journal of physical chemistry B
    Vol. 112, num. 6, p. 1718-1728
    DOI: 10.1021/jp077604a
    Date of publication: 2008-02
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Polarization effects on the dielectric properties of molten AgI

     Bitrian Varea, Vicente; Trullàs Simó, Joaquim
    Journal of physics: conference series
    Vol. 98, num. 04, p. 042006-1-042006-5
    DOI: 10.1088/1742-6596/98/4/042006
    Date of publication: 2008-01
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Long-wavelength limit of the static structure factors for mixtures of two simple molten salts with a common ion and generalized Bhatia-Thornton formalism: Molecular dynamics study of molten mixture Ag(Br0.7I0.3)

     Bitrian Varea, Vicente; Trullàs Simó, Joaquim; Silbert, Moises
    Physica B. Condensed matter
    Vol. 403, num. 23-24, p. 4249-4258
    DOI: 10.1016/j.physb.2008.09.017
    Date of publication: 2008-12
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • On the structure of the molten mixture Ag(I0.3Br0.7)

     Trullàs Simó, Joaquim; Bitrian Varea, Vicente; Kawakita, Y; Takeda, S; Enosaki, T; Silbert, Moises
    Journal of non-crystalline solids
    Vol. 353, num. 32-40, p. 2993-2996
    DOI: 10.1016/j.jnoncrysol.2007.05.069
    Date of publication: 2007-10
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Polarization effects on the structure of molten AgI in the long-wavelength limit

     Trullàs Simó, Joaquim
    Thirteenth International Conference on Liquid and Amorphous Metals
    Presentation's date: 2007-07-12
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • A polarizable ion model for the structure of molten AgI

     Bitrian Varea, Vicente; Trullàs Simó, Joaquim; Silbert, Moises
    Journal of chemical physics
    Vol. 126, num. 2, p. 021105-1-021105-4
    DOI: 10.1063/1.2432346
    Date of publication: 2007-01
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Molecular dynamics study of the incoherent and coherent contributions to the total dynamic structure factor of molten NaI

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of molecular liquids
    Vol. 136, num. 3, p. 227-235
    DOI: 10.1016/j.molliq.2007.08.022
    Date of publication: 2007-12
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Molecular dynamics study of polarizable point dipole models for molten sodium iodide

     Alcaraz Sendra, Olga; Bitrian Varea, Vicente; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 127, num. 15, p. 154508-1-154508-10
    DOI: 10.1063/1.2794044
    Date of publication: 2007-10
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Simulació per ordinador en matèria condensada. (Grup de recerca consolidat)

     Sese Castel, Gemma; Guardia Manuel, Elvira; Rey Oriol, Rosendo; Marti Rabassa, Jordi; Trullàs Simó, Joaquim
    Competitive project

     Share

  • Simulación por ordenador de sistemas condensados: sales fundidas, disoluciones iónicas y líquidos moleculares

     Sese Castel, Gemma; Guardia Manuel, Elvira; Rey Oriol, Rosendo; Marti Rabassa, Jordi; Trullàs Simó, Joaquim
    Competitive project

     Share

  • Molecular dynamics study of molten NaI. Coherent and incoherent contributions to the total structure factor.

     Trullàs Simó, Joaquim
    EMLG/JMLG Annual Meeting: Liquid Systems under Extrem Conditions
    Presentation's date: 2006-09-03
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Molecular dynamics study of polarizable ion models for molten AgBr

     Bitrian Varea, Vicente; Trullàs Simó, Joaquim
    Journal of physical chemistry B
    Vol. 110, p. 7490-7499
    DOI: 10.1021/jp056818u
    Date of publication: 2006-03
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Neutron diffraction data and molecular dynamics simulations of the molten mixture Ag(Br0.7I0.3)

     Bitrian Varea, Vicente; Silbert, Moises; Trullàs Simó, Joaquim; Enosaki, T; Kawakita, Y; Takeda, S
    Journal of chemical physics
    Vol. 125, num. 18, p. 184510-1-184510-10
    DOI: 10.1063/1.2386161
    Date of publication: 2006-11
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • AgBr: Potentials, structure and ionic transport

     Trullàs Simó, Joaquim
    6th Liquid Matter Conference
    Presentation's date: 2005-06-02
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Física per a estudiants d'informàtica

     Giro Roca, Antoni; Canales Gabriel, Manel; Rey Oriol, Rosendo; Sese Castel, Gemma; Trullàs Simó, Joaquim
    Date of publication: 2005-12
    Book

     Share Reference managers Reference managers Open in new window

  • On the structure of molten (AgI)0.3(AgBr)0.7 liquid mixture at T=650 C

     Trullàs Simó, Joaquim; Bitrian Varea, Vicente; Kawakita, Y; Takeda, S; Enosaki, T; Silbert, Moises
    Twelfth International Conference on Liquid and Amorphous Metals
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Structure and dynamics of molten AgCl: the inclusion of induced polarization

     Trullàs Simó, Joaquim; Alcaraz Sendra, Olga; ENRIQUE GONZALEZ TESEDO, LUIS; Silbert, Moises
    Journal of physical chemistry B
    Vol. 107, num. 1, p. 282-290
    DOI: 10.1021/jp026118e
    Date of publication: 2003
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Three sets of molecular dynamics simulations have been carried out to study the static structure and transport properties of molten AgCl at 1073 K. The first uses the Vashishta-Rahman rigid-ion potential (R-VR). The other two are polarizable ion potentials, which consist of the Vashishta-Rahman (P-VR) or the Born-Mayer (P-BM) rigid-ion potentials to which the anion-induced dipole polarization contributions are added. Both polarized model potentials reproduce well the main features of the structure of molten AgCl, including the characteristic three-peak feature present in the experimental broad principal peak of its total structure factor; this is not present in the R-VR simulations. The two polarized model potentials differ significantly in the way they account for the transport properties of the melt, by the mean square displacements, the velocity correlation functions, self-diffusion coefficients, or the ionic conductivity. In the case of the latter, the experimental result (ó ) 4.7 (¿âcm)-1) is bracketed between the R-VR (ó ) 5.8 (¿âcm)-1) and the P-VR (ó ) 4.0 (¿âcm)-1) values, with the P-BM value (ó ) 1.3 (¿âcm)-1) significantly lower.

  • Molecular dynamics simulation of collective motions in binary liquids

     Anento Moreno, Napoleon; Padro Cardenas, Joan Angel; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Molecular simulation
    Vol. 29, num. 6-7, p. 373-384
    DOI: 10.1080/0892702031000117171
    Date of publication: 2003-06
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Collective dynamic properties of different kind of binary liquid mixtures have been investigated by molecular dynamics simulation. The study includes both the longitudinal and the transverse current spectra in simple liquid alloys, 1:1 molten salts and liquid binary mixtures of neutral particles with an ionic-like structure. These systems were chosen as representative of binary liquids with different static structures in order to analyse the effects of structural ordering on the mechanisms of dynamic collective properties. The effect of the mass asymmetry between the two species in the mixture has been also discussed from the results for two different mass ratios for each kind of structure. Two length scales have been considered. On the one hand, the hydrodynamic scale (low wave numbers), where the modes for the partial currents of the two species are characterised by very close frequencies. On the other hand, the molecular scale (higher wave numbers), where the characteristic frequencies for the two species show noticeable differences. Vibrational concentration current modes (optic modes) have been found in neutral mixtures though their influence is rather weak, being the collective dynamic properties of this kind of systems dominated by the mass current modes (acoustic modes). On the contrary, in mixtures of charged particles such as molten salts the contribution of the concentration (charge) currents to the collective dynamics is important and optic modes can be characterised by a well-defined frequency for a wide range of wave numbers. It has been observed that heavy particles have a more relevant role on the mass current correlations whereas light particles play a dominant role on the concentration current correlations. The overall results for the three kinds of liquid mixtures analysed in this paper show that both the longitudinal and transverse current spectra are little dependent on the static structure of the system whereas marked differences are revealed when the particles in the system are either neutral or carry an electric charge.

  • Molecular dynamics simulations of collective motions in binary liquids

     Anento Moreno, Napoleon; Padro Cardenas, Joan Angel; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Molecular simulation
    Vol. 29, p. 373-384
    DOI: 10.1080/0892702031000117171
    Date of publication: 2003-06
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Simulación por ordenador de sistemas condensados: líquidos iónicos, polímeros y líquidos moleculares

     Guardia Manuel, Elvira; Sese Castel, Gemma; Marti Rabassa, Jordi; Trullàs Simó, Joaquim
    Competitive project

     Share

  • Física

     Giro Roca, Antoni; Canales Gabriel, Manel; Rey Oriol, Rosendo; Sese Castel, Gemma; Trullàs Simó, Joaquim
    Date of publication: 2003-09
    Book

     Share Reference managers Reference managers Open in new window

  • Structure and dynamics of molten AgCl. The inclusion of induced polarization

     Trullàs Simó, Joaquim; Alcaraz Sendra, Olga; Gonzalez, L E; Silbert, Moises
    Journal of physical chemistry B
    Vol. 107, num. 1, p. 282-290
    Date of publication: 2003-01
    Journal article

     Share Reference managers Reference managers Open in new window

  • Grup de recerca consolidat. Grup de simulació per ordinador en matèria condensada

     Sese Castel, Gemma; Guardia Manuel, Elvira; Giro Roca, Antoni; Rey Oriol, Rosendo; Trullàs Simó, Joaquim
    Competitive project

     Share

  • Journal of chemical physics

     Trullàs Simó, Joaquim
    Collaboration in journals

     Share

  • The structure of molten AgCl revisited

     Trullàs Simó, Joaquim; Alcaraz Sendra, Olga; Silbert, Moises
    Journal of non-crystalline solids
    Vol. 312-314, p. 438-442
    Date of publication: 2002-09
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    We have studied the total structure of molten AgCl at 1073 K by means of two polarizable ion models via molecular dynamics simulations. The model potentials consisted of either the Vashishta–Rahman (VR) or the Born–Mayer rigidion potentials to which the anion-induced polarization contribution is added. Both model potentials reproduce well the main features of the structure of molten AgCl with that using the VR model potential giving marginally better results.

  • Space-dependent self-diffusion processes in molten copper halides: A molecular dynamics study

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 115, p. 7071-7075
    DOI: 10.1063/1.1401827
    Date of publication: 2001
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • The bridge functions of molten salts

     Tasseven, Çetin; Enrique González, Luis; Silbert, Moises; Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 115, num. 10, p. 4676-4680
    DOI: 10.1063/1.1392366
    Date of publication: 2001
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Estudi de sals foses mitjançant la dinàmica molecular  Open access

     Alcaraz Sendra, Olga
    Department of Physics and Nuclear Engineering, Universitat Politècnica de Catalunya
    Theses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    El treball Estudi de sals foses mitjançant la dinàmica molecular està integrat dins la línia de recerca Simulació de comportament atòmic en la matèria condensada i amb ell s'han assolit dos grans objectius. El primer consisteix en completar l'estudi de les sals foses binàries d'ions monovalents (sals 1:1), que ja s'havia iniciat en aquest grup de recerca, amb l'estudi del AgCl, AgBr i dels halurs de tal·li (TlCl, TlBr i TlI). El segon és ampliar l'estudi de la dinàmica col·lectiva dels halurs de coure fosos amb l'estudi de les fluctuacions locals de les densitats parcials de partícules, de massa i de càrrega, i dels seus corrents longitudinals i transversals. Els resultats corresponents els presentem per separat en la part I i II de la memòria.Comencem la primera part amb el capítol 1, fent una introducció a les sals 1:1 foses que havien estat estudiades anteriorment, és a dir, els halurs alcalins i els halurs de coure i el AgI. Posem de relleu les característiques principals d'aquestes sals i expliquem els models que s'han utilitzat per estudiar-les.En el segon capítol proposem un mètode per determinar els factors d'estructura estàtics, que permet optimitzar el temps de càlcul i alhora obtenir unes funcions sense gaire soroll. El fet de disposar de bons factors d'estructura estàtics permet la comparació amb resultats experimentals de difracció elàstica de neutrons. A més a més, en aquest capítol aprofitem per descriure a l'espai recíproc les propietats estructurals dels halurs alcalins i de coure fosos. En els capítols tercer i quart, presentem els resultats de la dinàmica molecular del AgCl i el AgBr, i dels halurs de tal·li, respectivament. Aquestes sals s'han modelat considerant els potencials proposats conjuntament amb els Drs. Moises Silbert i Çetin Tasseven de la Universitat de East Anglia. Aquests potencials permeten reproduir bastant bé els factors d'estructura i les conductivitats iòniques experimentals. L'anàlisi de les funcions de distribució radial i els factors d'estructura estàtics, així com de les funcions de correlació de velocitats i els desplaçaments quadràtics mitjans, mostra que aquestes sals tenen un comportament intermedi entre els halurs alcalins (on els anions i cations tenen una mida molt semblant) i els halurs de coure (on els cations són molt més petits que els anions). També hem fet un estudi de la influència de la massa i la mida dels ions en la seva dinàmica individual.A la Part II del treball, per tal d'estudiar les fluctuacions de densitat i dels corrents en els halurs de coure fosos hem triat el CuCl i el CuI. En el CuCl els ions més grans (els anions) són més lleugers que els cations, en canvi, en el CuI són més pesants. A més a més, aquest estudi l'hem completat amb dos halurs alcalins com el KCl i el RbCl. En aquestes dues sals els cations i els anions són de mida semblant, però mentre que en el RbCl els anions són més lleugers que els cations, en el KCl tenen quasi la mateixa massa. D'aquesta manera podem veure quina és la influència de la massa i la mida en aquestes propietats.En el capítol cinc estudiem el procés d'autodifusió dels ions mitjançant les funcions de scattering intermèdies self i els seus espectres, anomenats factors d'estructura dinàmics self. A l'últim apartat comparem els resultats de les nostres simulacions per al CuCl amb els resultats experimentals de difracció quasielàstica de neutrons obtinguts pel Dr. Spencer Howells del Rutherford Appleton Laboratory.El capítol sis l'hem dedicat a les fluctuacions de densitat en sals 1:1 foses mitjançant les funcions de scattering intermèdies i els corresponents factors d'estructura dinàmics. Aquestes funcions revelen la presència de modes col·lectius acústics i òptics associats a les fluctuacions de la densitat de massa i de càrrega, respectivament. Aquests modes són una reminiscència dels modes acústic i òptic a l'estat sòlid.En el capítol set estudiem de les correlacions entre els corrents longitudinals i transversals, així com dels modes col·lectius que hi estan relacionats.Finalment presentem les conclusions i les perspectives de continuació d'aquest treball. A més a més, hem inclòs cinc apèndix on fem un recull argumentat de totes les definicions de les propietats que hem calculat.

  • The structure of molten AgCl revisited

     Trullàs Simó, Joaquim; Silbert, Moises
    Eleventh International Conference on Liquid and Amorphous Metals
    p. 99
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • The bridge functions of molten salts

     Trullàs Simó, Joaquim; Tasseven, C; González, L E; Silbert, Moises; Alcaraz Sendra, Olga
    Journal of chemical physics
    Vol. 115, num. 10, p. 4678-4680
    Date of publication: 2001-09
    Journal article

     Share Reference managers Reference managers Open in new window

  • Space-dependent self-diffusion processes in molten copper halides. A molecular dynamics study

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 115, num. 15, p. 7071-7075
    Date of publication: 2001-10
    Journal article

     Share Reference managers Reference managers Open in new window

  • Mass and size dependence of single ion dynamics in molten monohalides

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 113, num. 23, p. 10635-10641
    DOI: 10.1063/1.1323978
    Date of publication: 2000
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Grup de simulació per ordinador en materia condensada

     Guardia Manuel, Elvira; Sese Castel, Gemma; Giro Roca, Antoni; Rey Oriol, Rosendo; Marti Rabassa, Jordi; Trullàs Simó, Joaquim
    Competitive project

     Share

  • Simulación por ordenador de sistemas condensados: líquidos iónicos y moleculares.

     Guardia Manuel, Elvira; Sese Castel, Gemma; Giro Roca, Antoni; Marti Rabassa, Jordi; Trullàs Simó, Joaquim
    Competitive project

     Share

  • Mass and size dependence of single ion dynamics in molten monohalides

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    Journal of chemical physics
    Vol. 113, num. 23, p. 10635-10641
    Date of publication: 2000-12
    Journal article

     Share Reference managers Reference managers Open in new window

  • Velocity cross-correlations in Lennard Jones and soft-sphere fluids: a molecular dynamics simulation study

     Verdaguer, Albert; Padro Cardenas, Joan Angel; Trullàs Simó, Joaquim
    Journal of molecular liquids
    Vol. 85, num. 1-2, p. 23-32
    Date of publication: 2000-04
    Journal article

     Share Reference managers Reference managers Open in new window

  • Challenges in molecular simulation: bridging the length and time scale gap

     Trullàs Simó, Joaquim; Sese Castel, Gemma; Frenkel ., Daan; Rey Oriol, Rosendo; Ciccotti ., Giovanni; Mareschal ., Michel
    Competitive project

     Share

  • Collective dynamics in molten KCl, RbCl, CuCl and CuI: A molecular dynamics study

     Alcaraz Sendra, Olga; Trullàs Simó, Joaquim
    4th Liquid Matter Conference
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window