1,540 research outputs found
Rotational Spectroscopy of Nonafluoro-tert-butyl Alcohol
Nonafluoro-tert-butyl alcohol (NFTBA) is an alcohol being used in medicine and for the analysis of physiochemical and biological properties. Quantum chemical calculations on NFTBA were carried out using cluster computers from the Texas Advanced Computing Center (TACC) at Austin, TX. We scanned the C–C–O–H dihedral angle for 36 steps with each step at 10 degrees at the B3LYP/aug-cc-pVTZ level in order to identify the stable conformations and the energy barriers. The geometry of nonafluoro-tert-butyl was studied using MP2 and B3LYP Density Functional Theory (DFT) with an aug-cc- pVTZ basis set. The calculated rotational constants and dipole moments were used to help interpretation of the experimental study of nonafluoro-tert-butyl alcohol using microwave spectroscopy. We anticipate that large amplitude motions would occur on the alcohol group which may further perturb its rotational spectrum. The measured spectrum shows a very strong intensity of rotational transitions
Communication: Unambiguous comparison of many-electron wavefunctions through their overlaps
© 2016 Author(s). A simple and powerful method for comparing many-electron wavefunctions constructed at different levels of theory is presented. By using wavefunction overlaps, it is possible to analyze the effects of varying wavefunction models, molecular orbitals, and one-electron basis sets. The computation of wavefunction overlaps eliminates the inherent ambiguity connected to more rudimentary wavefunction analysis protocols, such as visualization of orbitals or comparing selected physical observables. Instead, wavefunction overlaps allow processing the many-electron wavefunctions in their full inherent complexity. The presented method is particularly effective for excited state calculations as it allows for automatic monitoring of changes in the ordering of the excited states. A numerical demonstration based on multireference computations of two test systems, the selenoacrolein molecule and an iridium complex, is presented
Magnetization dynamics: path-integral formalism for the stochastic Landau-Lifshitz-Gilbert equation
We construct a path-integral representation of the generating functional for
the dissipative dynamics of a classical magnetic moment as described by the
stochastic generalization of the Landau-Lifshitz-Gilbert equation proposed by
Brown, with the possible addition of spin-torque terms. In the process of
constructing this functional in the Cartesian coordinate system, we critically
revisit this stochastic equation. We present it in a form that accommodates for
any discretization scheme thanks to the inclusion of a drift term. The
generalized equation ensures the conservation of the magnetization modulus and
the approach to the Gibbs-Boltzmann equilibrium in the absence of non-potential
and time-dependent forces. The drift term vanishes only if the mid-point
Stratonovich prescription is used. We next reset the problem in the more
natural spherical coordinate system. We show that the noise transforms
non-trivially to spherical coordinates acquiring a non-vanishing mean value in
this coordinate system, a fact that has been often overlooked in the
literature. We next construct the generating functional formalism in this
system of coordinates for any discretization prescription. The functional
formalism in Cartesian or spherical coordinates should serve as a starting
point to study different aspects of the out-of-equilibrium dynamics of magnets.
Extensions to colored noise, micro-magnetism and disordered problems are
straightforward.Comment: 47 pages + appendix, published versio
Between Region and Nation: Family farming public policy process in MERCOSUR – The case of National Registers on Family Farming
Se analiza el proceso de construcción de las polÃticas públicas regionales (PPR) en el ámbito de la Reunión Especializada de Agricultura Familiar (REAF) del MERCOSUR con el objetivo de reconocer las particularidades de este proceso en el ámbito regional e identificar los diferentes actores y actoras (con sus particulares necesidades, intereses, valores e ideas) involucradas en él. Se pone el foco en el caso de los Registros Nacionales de Agricultura Familiar en tanto a) ha resultado una PPR exitosa cuya elaboración ha involucrado un amplio número de actores y actoras y b) a diferencia de lo que ocurre con otras PPR en la REAF, para el caso de los Registros se ha llevado adelante un proceso inédito de evaluación y reelaboración de la polÃtica a nivel regional. De esta forma, se busca contribuir al estudio de las PPR planteando preguntas en torno de las posibilidades y limitaciones de la región para funcionar como un espacio de elaboración, implementación y evaluación de polÃticas públicas. En términos metodológicos se recurre a investigación documental, entrevistas a actoras y actores clave e instancias de observación participante.The article analyzes the regional public policies (PPR) process in the Specialized Meeting on Family Farming (REAF) in MERCOSUR, recognizing the particularities of this process at the regional level and identifying the different actors and the needs, interests, values and ideas involved on it. It focuses on the case of the National Registers of Family Farmers, as a) it has been a successful PPR whose elaboration hasinvolved a large number of actors and b) it implied a process of evaluation and rethinking of the policy at the regional level. In this way, it seeks to contribute to the study of PPRs by posing questions about the possibilities and limitations of the region to function as a space for the elaboration, implementation, and evaluation of public policies. Methodology is based on documental research, interviews to key actors and participant observation.Centro de Investigación en EconomÃa y ProspectivaFil: Gonzalez, Leticia. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Centro de Investigación en EconomÃa y Prospectiva (CIEP); Argentin
Acción social colectiva y procesos de integración regional en Sudamérica: la participación de las organizaciones de la agricultura familiar en la construcción y el devenir de la Reunión Especializada de Agricultura Familiar del MERCOSUR (2004-2012)
Tesis para obtener el grado de MagÃster en Estudios Latinoamericanos, presentada en Facultad de Humanidades, Universidad Nacional de San MartÃn en 2018En esta investigación se analiza la participación de las organizaciones de la agricultura familiar en la Reunión Especializada de Agricultura Familiar (REAF) del MERCOSUR para determinar cuáles han sido los aportes de los actores y las actoras sociales al proceso de construcción de polÃticas públicas regionales para el sector y, consecuentemente, al proceso de construcción del bloque como un espacio para el desarrollo de la región.This research analyzes the participation of family farming organizations in the Family Farming Specialized Meeting of MERCOSUR (REAF) in order to determine the contributions of the social actors to the public policy process and, consequently, to the region building process as a space for development.Instituto de Investigación en Prospectiva y PolÃticas PúblicasFil: Gonzalez, Leticia. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de Prospectiva y PolÃticas Públicas; Argentin
Acción social colectiva y procesos de integración regional en Sudamérica
El presente texto es un resumen de la tesis presentada por la autora para obtener el grado de MagÃster en Estudios Latinoamericanos, con el tÃtulo: Acción colectiva y procesos de integración regional en Sudamérica: la participación de las organizaciones de agricultura familiar en la construcción y el devenir de la reunión especializada de agricultura familiar del Mercosur (2004-2012). Fue dirigida por la Dra. Daniela Vanesa Perrotta y defendida el 28 de noviembre de 2018.Instituto de Investigación en Prospectiva y PolÃticas PúblicasFil: Gonzalez, Leticia. Instituto Nacional de TecnologÃa Agropecuaria (INTA). Instituto de Prospectiva y PolÃticas Públicas; Argentin
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