Browsing DFA  Artículos by Issue Date
Now showing items 2140 of 216

Computer simulation study of the global phase behavior of linear rigid LennardJones chain molecules : comparison with flexible models
(American Institute of Physics, 2004)The global phase behavior ~i.e., vaporliquid and fluidsolid equilibria! of rigid linear LennardJones ~LJ! chain molecules is studied. The phase diagrams for threecenter and fivecenter rigid model molecules are ... 
Phase Diagram of the ProtonNeutron Interacting Boson Model
(American Physical Society, 2004)We study the phase diagram of the protonneutron interacting boson model with special emphasis on the phase transitions leading to triaxial phases. The existence of a new critical point between spherical and triaxial shapes ... 
Testarea simulation method for the direct determination of the interfacial tension of systems with continuous or discontinuous potentials
(American Institute of Physics, 2005)A novel testarea TA technique for the direct simulation of the interfacial tension of systems interacting through arbitrary intermolecular potentials is presented in this paper. The most commonly used method invokes ... 
Dipole moment and intensities in the electronic ground state of NH3: Bridging the gap between ab initio theory and spectroscopic experiment
(American Institute of Physics, 200503)We report here theoretical values for the transition moments of an extensive set of vibrational bands in the electronic ground state of 14NH3. For selected bands, we have further made detailed simulations of the rotational ... 
Finitesize scaling exponents in the interacting boson model
(American Physical Society, 20050714)We investigate the finitesize scaling exponents for the critical point at the shape phase transition from U(5) (spherical) to O(6) (deformed unstable) dynamical symmetries of the Interacting Boson Model, making use ... 
The β 4 potential at the U(5)–O(6) critical point of the Interacting Boson Model
(American Physical Society, 20050908)Exact numerical results of the interacting boson model Hamiltonian along the integrable line from U(5) to O(6) are obtained by diagonalization within boson seniority subspaces. The matrix Hamiltonian reduces to a block ... 
Scattering of (6)He at energies around the Coulomb barrier
(Institute of Physics, 20050912)We have measured elastic cross sections of the scattering of 6He at ELab = 14, 16, 17, 18, 22 MeV on 208Pb in the angular ranges of 20± − 64± and 135± − 170±. A significant amount of 4He events is found at energies well ... 
A theoretical description of energy spectra and twoneutron separation energies for neutronrich zirconium isotopes
(Springer, 200511)Very recently the atomic masses of neutronrich Zr isotopes, from 96Zr to 104Zr, have been measured with high precision. Using a schematic Interacting Boson Model (IBM) Hamiltonian, the evolution from spherical to deformed ... 
Continuous unitary transformations in twolevel boson systems
(American Physical Society, 20051230)Twolevel boson systems displaying a quantum phase transition from a spherical (symmetric) to a deformed (broken) phase are studied. A formalism to diagonalize Hamiltonians with O(2L + 1) symmetry for large number of ... 
Coulomb breakup in a transformed harmonic oscillator basis
(American Physical Society, 2006)The problem of Coulomb breakup in the scattering of a twobody loosely bound projectile by a heavy target is addressed. A basis of transformed harmonic oscillator (THO) wave functions is used to discretize the ... 
The nature of the calculation of the pressure in molecular simulations of continuous models from volume perturbations
(American Institute of Physics, 2006)We consider some fundamental aspects of the calculation of the pressure from simulations by performing volume perturbations. The method, initially proposed for hardcore potentials by Eppenga and Frenkel Mol. Phys. 52, ... 
A scalar twolevel boson model to study the IBM phase diagram in the Casten triangle
(American Physical Society, 20060505)We introduce a simple twolevel boson model with the same energy surface as the Qconsistent Interacting Boson Model Hamiltonian. The model can be diagonalized for large number of bosons and the results used to check ... 
Surface tension of the most popular models of water by using the testarea simulation method
(American Institute of Physics, 2007)We consider the calculation of the surface tension from simulations of several models of water, such as the traditional TIP3P, SPC, SPC/E, and TIP4P models, and the new generation of TIP4Plike models including the ... 
Twolevel interacting boson models beyond the mean field
(American Physical Society, 20070102)The phase diagram of twolevel boson Hamiltonians, including the Interacting Boson Model (IBM), is studied beyond the standard mean field approximation using the HolsteinPrimakoff mapping. The limitations of the usual ... 
α particle particle production in the scattering of He6 by Pb208 at energies around the Coulomb barrier
(Elsevier, 20070801)New experimental data from the scattering of 6He + 208Pb at energies around and below the Coulomb barrier are presented. The yield of breakup products coming from projectile fragmentation is dominated by a strong group of ... 
Observation of twoproton radioactivity of (19)Mg by tracking the decay products
(American Physical Society, 20071102)We have observed the twoproton radioactivity of the previously unknown 19Mg groundstate by tracking the decay products in°ight. For the ¯rst time, the trajectories of the 2pdecay products, 17Ne+p+p, have been measured ... 
Reinvestigation of the ground and first torsional state of methylformate
(Elsevier, 200712)We have reinvestigated the laboratory spectrum for the methylformate HCOOCH3 molecule involving both the ground and first excited torsional states. We have fitted within almost experimental accuracy a data set for this ... 
Algebraic approach to twodimensional systems : shape phase transitions, monodromy, and thermodynamic quantities
(American Physical Society, 2008)We analyze shape phase transitions in twodimensional algebraic models. We apply our analysis to linearto bent transitions in molecules and point out what observables are particularly sensitive to the transition ... 
Vapor–liquid and liquid–liquid phase equilibria of mixtures containing square‐well molecules by Gibbs ensemble Monte Carlo simulation
(American Institute of Physics, 2008)Gibbs ensemble Monte Carlo simulations are undertaken in order to determine the vapor–liquid and liquid–liquid phase equilibria for mixtures containing square‐well particles. Two types of binary systems are examined, namely, ... 
Determination of the melting point of hard spheres from direct coexistence simulation methods
(American Institute of Physics, 2008)We consider the computation of the coexistence pressure of the liquidsolid transition of a system of hard spheres from direct simulation of the inhomogeneous system formed from liquid and solid phases separated by an ...