Search results for "SCF"
showing 10 items of 40 documents
Nuovi materiali per celle a combustibile ad ossidi solidi a temperatura intermedia (IT-SOFC): sintesi, caratterizzazione e correlazione struttura-pro…
2014
Design of carborane molecular architectures with electronic structure computations: From endohedral and polyradical systems to multidimensional netwo…
2009
11 pags, 6 figs. -- 19th International Conference on Physical Organic Chemistry (ICPOC-19) 13–18 July 2008, Santiago de Compostela, Spain
Skandija trifluorīda struktūras pētīšana, izmantojot molekulāro dinamiku
2016
Skandija fluorīds (ScF3) ir interesants materiāls, kuram plašā temperatūras diapazonā no 10 līdz 1100 K piemīt negatīvā termiskā izplešanās. Šī darbā ietvaros tiek pētīta ScF3 režģa struktūra, izmantojot klasisko un ab initio molekulārās dinamikas (MD) pieeju CP2K programmas ietvaros. Darbā tika pārbaudīti dažādi MD aprēķinu parametri un aprēķinu rezultātu stabilitāte atkarībā no izvelētā ScF3 superšūnas izmēra un MD laika soļa lieluma, tika izpētīta vidējās režģa konstantes atkarība no temperatūras npT (izobāriska-izotermiska) ansamblī, iegūts leņķusadalījums Sc-F-Sc atomiem, Sc atoma radiālā sadalījuma funkcija, kā arī tika izstrādāti datu apstrādes programmatūras rīki. Rezultāti, kas ieg…
A surface hopping algorithm for nonadiabatic minimum energy path calculations
2015
The article introduces a robust algorithm for the computation of minimum energy paths transiting along regions of near-to or degeneracy of adiabatic states. The method facilitates studies of excited state reactivity involving weakly avoided crossings and conical intersections. Based on the analysis of the change in the multiconfigurational wave function the algorithm takes the decision whether the optimization should continue following the same electronic state or switch to a different state. This algorithm helps to overcome convergence difficulties near degeneracies. The implementation in the MOLCAS quantum chemistry package is discussed. To demonstrate the utility of the proposed procedur…
The metabolic responses to electrical pulse-induced contractions in C2C12 myotubes are greater in high glucose medium
2021
Osaa liikunnan terveyshyötyjen mekanismeista on vaikeaa tutkia ihmisillä tai koe-eläimillä. Viljeltyjen C2C12 myotuubien sähköpulssistimulaatiolla (EPS, engl. electrical pulse stimulation) voidaan mallintaa lihassupistuksia ja liikuntaa in vitro –olosuhteissa. EPS:n vaikutusta C2C12 myotuubien aineenvaihduntaan ei kuitenkaan tunneta tarkasti. Lisäksi C2C12 myotuubeja viljellään yleensä korkeassa ei-fysiologisessa 25 mM glukoosipitoisuudessa, mikä voi vaikuttaa EPS-vasteisiin. Tässä tutkimuksessa C2C12 myotuubeja sähköpulssistimuloitiin 24 tunnin ajan sekä matalan 5.5 mM (MG) että korkean 25 mM (KG) glukoosipitoisuuden olosuhteissa, ja aineenvaihduntatuotteiden konsentraatiot analysoitiin se…
Development of anode supported Single Chamber Solid Oxide Fuel Cells running in air/methane mixture
2013
International audience; Single Chamber Solid Oxide Fuel Cells (SCFC) show a growing interest and are the concern of more and more papers. In such device, anode and cathode are ex-posed to a gas mixture of fuel (hydrocarbon) and oxidant (air) so that no more sealing with electrolyte is necessary. Their operating principle is based on the different catalytic activities of anode and cathode: Ideally, the anode has to be active for the oxidation of fuel while the cathode should present only a strong electro-activity for oxygen reduction. In this paper, we present the development of an anode supported SCFC device running in air/methane mixture characterized by their volume ratio, Rmix = CH4/O2.
A theoretical study of the intramolecular charge transfer in 4-(dimethylamino)benzethyne
2014
We have investigated the non-adiabatic relaxation processes occurring in the singlet manifold of 4-(dimethylamino)benzethyne (DMABE){,} a molecule isoelectronic with 4-(dimethylamino)benzonitrile (DMABN) but lacking its characteristic dual fluorescence{,} using multireference perturbation theory methods. The results obtained point out to the existence of a two-fold decay mechanism in which the population of the initially accessed La state bifurcates towards a locally excited (LE) and a [small pi][sigma]* state. Further relaxation to an emitting intramolecular charge transfer (ICT) state is impeded due to the presence of pronounced energy barriers along their associated potential energy surf…
On the role of the triplet state in the cis/trans isomerization of rhodopsin: A CASPT2//CASSCF study of a model chromophore
2011
The possibility of population of the lowest-lying triplet state (T1) in the early events of the photochemical isomerization process of a model chromophore of Rhodopsin (Rh) has been analyzed using multireference perturbation theory (CASPT2//CASSCF) methods. It is shown that the characteristics of the isomerization process namely small S1−T1 gap, presence of hydrogen out of plane active vibrational modes, and existence of a dense manifold of vibrational states, render possible the fulfilment of the conditions needed for the population of T1. The possible consequences for the photochemistry and photophysics of Rh are also discussed. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111:3431–3…
Radiation damage in the DNA/RNA nucleobases: A theoretical study
2015
La comprensión de los mecanismos de daño en el DNA/RNA inducidos por luz UV y en condiciones de estrés reductor fue el principal objetivo de esta tesis. Para ello se usaron en monómeros y dímeros el método espacio activo complete campo autoconsistente / espacio activo completo teoría de perturbaciones hasta segundo orden de espacio activo complete(CASSCF/CASPT2) y estrategias computacionales precisas de determinación del camino de reacción. En cuanto al daño inducido por la luz UV en el ADN/ARN, hemos estudiado la fotoproducción de dímeros de pirimidina ciclobutano (CPDs) en nucleobases apiladas a través de las vías singlet y triplete. Estos mecanismos de fotodimerización son iniciados por …
Theoretical and computational studies of magnetic anisotropy and exchange coupling in molecular systems
2018
The field of molecular magnetism studies the magnetic properties of molecular systems as opposed to conventional metal-based magnets. The high chemical modifiability of the constituting molecules makes such materials highly versatile, and the small size of the building blocks leads to the rise of various quantum mechanical phenomena, such as tunneling and entanglement. These phenomena can then be further utilized in the construction of nanoscale quantum devices. This dissertation describes computational and theoretical studies in the field of molecular magnetism using state-of-the-art quantum chemical methods based on ab initio multireference approaches and broken symmetry density functional t…