Now showing items 1-20 of 35

• #### Adaptive multi-stage integrators for optimal energy conservation in molecular simulations ﻿

(2016-10-01)
We introduce a new Adaptive Integration Approach (AIA) to be used in a wide range of molecular simulations. Given a simulation problem and a step size, the method automatically chooses the optimal scheme out of an available ...
• #### Adaptive Splitting Integrators for Enhancing Sampling Efficiency of Modified Hamiltonian Monte Carlo Methods in Molecular Simulation ﻿

(2017-10-24)
The modified Hamiltonian Monte Carlo (MHMC) methods, i.e., importance sampling methods that use modified Hamiltonians within a Hybrid Monte Carlo (HMC) framework, often outperform in sampling efficiency standard techniques ...
• #### Assessment of van der Waals inclusive density functional theory methods for layered electroactive materials ﻿

(2017-01-01)
Computational-driven materials discovery requires efficient and accurate methods. Density functional theory (DFT) meets these two requirements for many classes of materials. However, DFT-based methods have limitations. One ...
• #### Atomistic Insight into Ion Transport and Conductivity in Ga/Al-Substituted Li$_7$La$_3$Zr$_2$O$_{12}$ Solid Electrolytes ﻿

(2018-01-09)
Garnet-structured Li$_{7}$La$_{3}$Zr$_{2}$O$_{12}$ is a promising solid electrolyte for next-generation solid-state Li batteries. However, sufficiently fast Li-ion mobility required for battery applications only emerges ...
• #### Causality, 'superluminality', and reshaping in undersized waveguides ﻿

(2012-12-31)
We analyse the reshaping mechanism leading to apparently 'superluminal' advancement of a pulse traversing an undersized section of a waveguide. For frequencies below the first inelastic threshold (cut off one), there are ...
• #### Classification of resonance Regge trajectories and a modified Mulholland formula ﻿

(2011-12-31)
We employ a simple potential model to analyze the effects which a Regge trajectory, correlating with a bound or a metastable state at zero angular momentum, has on an integral cross section. A straightforward modification ...
• #### Combining stochastic and deterministic approaches within high efficiency molecular simulations ﻿

(2013-12-31)
Generalized Shadow Hybrid Monte Carlo (GSHMC) is a method for molecular simulations that rigorously alternates Monte Carlo sampling from a canonical ensemble with integration of trajectories using Molecular Dynamics (MD). ...
• #### Complex angular momentum theory of state-to-state integral cross sections: Resonance effects in the $F + HD \to HF(v' = 3) + D$ reaction ﻿

(2015-12-31)
State-to-state reactive integral cross sections (ICSs) are often affected by quantum mechanical resonances, especially near a reactive threshold. An ICS is usually obtained by summing partial waves at a given value of ...
• #### Computer software for understanding resonances and resonance-related phenomena in chemical reactions ﻿

(2014-12-31)
In numerical modelling of chemical reactions one calculates the scattering matrix for the required values of energy and angular momentum. Having done so, one still faces the non-trivial task of extracting detailed information ...
• #### Constant pressure hybrid Monte Carlo simulations in GROMACS ﻿

(2014-12-31)
Adaptation and implementation of the Generalized Shadow Hybrid Monte Carlo (GSHMC) method for molecular simulation at constant pressure in the NPT ensemble are discussed. The resulting method, termed NPT-GSHMC, combines ...
• #### Dynamic modeling of the morphology of latex particles with in situ formation of graft copolymer ﻿

(2012-12-31)
Modification of the polymer-polymer interfacial tension is a way to tailor-make particle morphology of waterborne polymer-polymer hybrids. This allows achieving a broader spectrum of application properties and maximizing ...
• #### Dynamic modeling of the morphology of multiphase waterborne polymer particles ﻿

(2013-12-31)
Multiphase waterborne polymer particles provide advantages in more demanding applications, and their performance depends on particle morphology. Currently, no dynamic model for the prediction of the development of the ...
• #### Enhancing sampling in atomistic simulations of solid state materials for batteries: a focus on olivine NaFePO$_4$ ﻿

(2017-03-07)
The study of ion transport in electrochemically active materials for energy storage systems requires simulations on quantum-, atomistic- and meso-scales. The methods accessing these scales not only have to be effective but ...
• #### An even simpler understanding of quantum weak values ﻿

(2018-01)
We explain the properties and clarify the meaning of quantum weak values using only the basic notions of elementary quantum mechanics.
• #### Exploring Li-ion conductivity in cubic, tetragonal and mixed-phase Al-substituted Li7La3Zr2O12 using atomistic simulations and effective medium theory ﻿

(2019-08-15)
Garnet Li7La3Zr2O12 (LLZO) is a promising solid electrolyte candidate for solid-state Li-ion batteries, but at room temperature it crystallizes in a poorly Li-ion conductive tetragonal phase. To this end, partial substitution ...
• #### Extracting S-matrix poles for resonances from numerical scattering data: Type-II Padé reconstruction ﻿

(2011-12-31)
We present a FORTRAN 77 code for evaluation of resonance pole positions and residues of a numerical scattering matrix element in the complex energy (CE) as well as in the complex angular momentum (CAM) planes. Analytical ...
• #### Hartman effect and weak measurements that are not really weak ﻿

(2011-12-31)
We show that in wave packet tunneling, localization of the transmitted particle amounts to a quantum measurement of the delay it experiences in the barrier. With no external degree of freedom involved, the envelope of the ...
• #### Impact of competitive processes on controlled radical polymerization ﻿

(2014-12-31)
The kinetics of radical polymerization have been systematically studied for nearly a century and in general are well understood. However, in light of recent developments in controlled radical polymerization many kinetic ...
• #### Interference mechanism of seemingly superluminal tunneling ﻿

(2013-12-31)
Apparently "superluminal" transmission, e.g., in quantum tunneling and its variants, occurs via a subtle interference mechanism which allows reconstruction of the entire spatial shape of a wave packet from its front tail. ...
• #### Meso-GSHMC: A stochastic algorithm for meso-scale constant temperature simulations ﻿

(2011-12-31)
We consider the problem of time-stepping/sampling for molecular and meso-scale particle dynamics. The aim of the work is to derive numerical time-stepping methods that generate samples exactly from the desired target ...