Article
Multidisciplinary Sciences
Jan Kessler, Francesco Calcavecchia, Thomas D. Kuehne
Summary: Inspired by the universal approximation theorem and the widespread adoption of artificial neural network techniques, feed-forward neural networks are proposed as a general purpose trial wave function for quantum Monte Carlo simulations of continuous many-body systems. The accuracy of the trial wave functions was demonstrated by studying an exactly solvable model system of two trapped interacting particles and the hydrogen dimer. The whole many-body wave function can be represented by a neural network for simple model systems, while the antisymmetry condition of non-trivial fermionic systems is incorporated by means of a Slater determinant.
ADVANCED THEORY AND SIMULATIONS
(2021)
Article
Polymer Science
Joao C. O. Guerra, Antonio Cadilhe
Summary: The presence of defects and dirt in actual substrates affects their properties, breaking symmetries and reducing spatial dimensionality. The study shows novel behavior of polymer mass transport on a crystalline substrate when a single attractive impurity is present. The diffusion coefficient is found to have size scaling dependence with the number of monomers in the polymer.
Article
Chemistry, Physical
Grzegorz Ziolkowski, Dariusz Chrobak, Grazyna Chelkowska, Ondrej Zivotsky, Artur Chrobak
Summary: The paper discusses Monte Carlo magnetic simulations for fractal-like nano and mesoscopic grains, showing that the size effects depend on the chosen value of magnetic anisotropy. For fractals with ultra-high coercivity, decreasing their size leads to deterioration of coercivity, especially for high surface to volume ratio, while soft magnetic fractals exhibit the opposite effect with the appearance of coercive field and significantly higher energy product than conventional rare earths' free permanent magnets.
Article
Engineering, Geological
Bak Kong Low
Summary: This paper investigates the context-dependent sensitivities of parameters and the reliability-based design (RBD) of rock slopes. It compares the design points in RBD with those of partial factor design methods and demonstrates that partial factors from the first-order reliability method (FORM) can provide case-specific insights and guidance to partial factor design methods like Eurocode 7 (EC7) and load and resistance factor design (LRFD). The paper suggests that conducting RBD-via-FORM in tandem with partial factor designs is more illuminating and meaningful than calibrating partial factors of parameters.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Physics, Multidisciplinary
Elena N. Govorun, Ruslan M. Shupanov, Sophia A. Pavlenko, Alexei R. Khokhlov
Summary: The paper discusses the use of conformation-dependent design of polymer sequences to control macromolecular self-assembly, considering different microphase-separated morphologies. It explores the application of this design in domains of different shapes through probability distributions and exponential asymptotes.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2021)
Article
Construction & Building Technology
Kaijian Zhang, Jianzhuang Xiao, Qingtian Zhang
Summary: The study conducted a time-dependent reliability analysis of cover cracking in recycled aggregate concrete (RAC) induced by reinforcement corrosion. Key factors influencing failure probability such as concrete strength, cover depth, corrosion rate were determined. Results showed failure probabilities of cover cracking and reaching limit crack width to be 3.34 x 10(-2) and 6.64 x 10(-2) respectively.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Biochemistry & Molecular Biology
Andrzej Patrykiejew
Summary: A simple lattice model was used to study the formation of multilayer films by fluids with orientation-dependent interactions on solid surfaces. The structure of multilayer films was found to depend on the strengths of surface potential felt by differently oriented particles and the interaction between the B halves of fluid particles. Finite temperature behavior was investigated through Monte Carlo simulation methods.
Article
Chemistry, Physical
Carsten Svaneborg, Ralf Everaers
Summary: We propose a computationally efficient multiscale method for preparing equilibrated, isotropic long-chain model polymer melts. The method involves Monte Carlo simulations for chain structure equilibration and theoretical insight from a constrained mode tube model for introducing bead degrees of freedom and random walk conformational statistics. The resulting chain statistics is in excellent agreement with literature results.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Owen Bradley, George G. Batrouni, Richard T. Scalettar
Summary: The Holstein Hamiltonian describes fermions interacting with phonons on a lattice. It predicts the behavior of dressed quasiparticles and the formation of superconducting and charge density wave phases at different densities. Quantum Monte Carlo calculations have been used to determine critical temperatures for these phase transitions in various lattice geometries.
Article
Materials Science, Multidisciplinary
S. Tarat, Bo Xiao, R. Mondaini, R. T. Scalettar
Summary: This paper investigates the two mechanisms for the vanishing of the sign problem in quantum simulations: whether randomly chosen field configurations have negative det[M(h)], or if the specific subset of configurations chosen by the weighting function have a greater preponderance of negative values. By conducting auxiliary field quantum Monte Carlo simulations of interacting fermions, the relative importance of these two mechanisms can be better understood.
Article
Materials Science, Multidisciplinary
P. Syam Prasad, Jyoti Ranjan Mohanty
Summary: Rare earth-transition metal alloys have attracted considerable attention in ultrafast and terahertz spintronics applications due to their interesting properties. This study investigates the temperature dependence of magnetic properties of amorphous ferrimagnetic TbCo by varying the compositions. The results show that the magnetic properties of amorphous TbCo can be easily tuned by varying their composition and have a strong temperature dependence.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Polymer Science
Jiang Zhang, Wenbing Hu
Summary: The effects of specific chain-end hydrogen-bonding interactions on the once-folding crystallization of 16-mers in PEG were investigated. It was found that these interactions have little influence on the kinetics of nucleation and lateral growth, but create a significant gap at the growth front, leading to the double-lamella phenomenon. The chain-end hydrogen-bonding interactions are abundant at the surfaces of once-folded lamellar crystals, enhancing their metastability and hindering their thickening into chain-extended crystals. Additionally, intra- and inter-molecular secondary nucleation at the folded and extended growth fronts exhibit different growth rate dependencies on the interaction strengths. The study reveals the role of specific chain-end interactions in PEG crystallization.
Article
Polymer Science
Russell K. W. Spencer, Mark W. Matsen
Summary: In this study, we critically reassessed off-lattice Monte Carlo simulations of athermal blends of stiff and flexible polymers next to a hard wall. Our improved simulations show that the flexible polymers actually have a long-range surface preference, contradicting the original simulations, experiments, and alternative calculations. This resolves a long-standing controversy and supports the predictions of mean-field theory regarding the concentration profile of the flexible polymer.
Article
Chemistry, Physical
Dilimulati Aierken, Michael Bachmann
Summary: We systematically investigate the effect of bending stiffness on the ground-state conformations of semiflexible polymers. The formation of different conformations depends strongly on the strength of the bending restraint, as observed through detailed analysis of contact and distance maps.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
Yifan Wang, Jake Kalscheur, Ya-Qiong Su, Emiel J. M. Hensen, Dionisios G. Vlachos
Summary: Understanding the evolution of the catalyst's structure under working conditions is challenging. The study introduces a multiscale modeling framework and machine learning to investigate the structures and nucleation of CeO2-supported Pd clusters and single atoms at different catalyst loadings, temperatures, and exposures to CO. Experimental data lacks simultaneous temporal and spatial resolution, hindering accurate structure determination.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
I. Kriuchevskyi, J. P. Wittmer, O. Benzerara, H. Meyer, J. Baschnagel
EUROPEAN PHYSICAL JOURNAL E
(2017)
Article
Chemistry, Physical
Edward R. Duranty, Jorg Baschnagel, Mark Dadmun
JOURNAL OF CHEMICAL PHYSICS
(2017)
Article
Chemistry, Physical
I. Tanis, H. Meyer, T. Salez, E. Raphael, A. C. Maggs, J. Baschnagel
JOURNAL OF CHEMICAL PHYSICS
(2017)
Article
Chemistry, Physical
C. Ruscher, A. N. Semenov, J. Baschnagel, J. Farago
JOURNAL OF CHEMICAL PHYSICS
(2017)
Article
Physics, Multidisciplinary
I. Kriuchevskyi, J. P. Wittmer, H. Meyer, J. Baschnagel
PHYSICAL REVIEW LETTERS
(2017)
Article
Instruments & Instrumentation
P. Chapuis, P. C. Montgomery, F. Anstotz, A. Leong-Hoi, C. Gauthier, J. Baschnagel, G. Reiter, G. B. McKenna, A. Rubin
REVIEW OF SCIENTIFIC INSTRUMENTS
(2017)
Article
Chemistry, Physical
L. Klochko, J. Baschnagel, J. P. Wittmer, A. N. Semenov
JOURNAL OF CHEMICAL PHYSICS
(2019)
Article
Chemistry, Physical
L. Klochko, J. Baschnagel, J. P. Wittmer, A. N. Semenov
Summary: This study suggests that time-dependent correlation functions related to temperature and energy in computer simulations of molecular systems may depend on the thermostatting mechanism used, but linear response functions should be considered as universal properties of physical systems. By deriving general expressions for frequency-dependent heat capacity, the precision of numerical calculations can be improved to reflect all relevant relaxation processes.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Gunter Reiter, Farzad Ramezani, Joerg Baschnagel
Summary: In this study, isothermal and temperature-sweep creep experiments were conducted on filaments derived from spin coated and subsequently crumpled thin polystyrene films. The filaments showed significant shrinkage due to residual stresses induced during preparation, and the shrinkage was monitored as a function of time at different temperatures. The influence of preparation conditions and subsequent annealing on the shrinkage and relaxation behavior of supported thin polymer films was also investigated. The results revealed a sequence of relaxation regimes during the temporal evolution of shrinkage. Comparisons with published results on drawn melt-spun fibers showed intriguing similarities between the two systems prepared along different pathways. The magnitudes of shrinkage in the melt-spun fibers and filaments from crumpled spin coated polymer films were found to be similar, suggesting the existence of generic mechanisms of forgetting in non-equilibrated polymers.
EUROPEAN PHYSICAL JOURNAL E
(2022)
Article
Chemistry, Physical
L. Klochko, J. Baschnagel, J. P. Wittmer, H. Meyer, O. Benzerara, A. N. Semenov
Summary: The spatiotemporal correlations of the local stress tensor in supercooled liquids are studied both theoretically and by molecular dynamics simulations. The results show that the dynamical structure factor and stress correlation tensor can be accurately described by the generalized shear and longitudinal relaxation moduli. Furthermore, a rigorous approach is developed to calculate the longitudinal relaxation modulus for low wave-vectors, taking into account the effect of bulk correlation functions, static structure factor, and thermal conductivity. The theoretical results are in excellent agreement with the simulation data.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
F. Demydiuk, M. Solar, H. Meyer, O. Benzerara, W. Paul, J. Baschnagel
Summary: The torsional potential of polymer chains plays a crucial role in determining their flexibility, segmental dynamics, and thermodynamic properties. In this study, molecular dynamics simulations were performed to investigate the effects of torsions on the conformational properties, thermodynamic quantities, and glass transition temperature of cis-trans-1,4-polybutadiene (PBD) melts. The results show that the influence of torsions on polymer conformations is weak, but it has a significant impact on the glass transition temperature.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
J. P. Wittmer, A. N. Semenov, J. Baschnagel
Summary: The strain correlation functions in two-dimensional isotropic elastic bodies are found to depend on the direction of the field vector and the orientation of the coordinate system. This dependence cannot be used to indicate anisotropy or plastic rearrangement. It is different for the associated strain response field containing information on the localized stress perturbation.
Article
Physics, Condensed Matter
C. Ruscher, S. Ciarella, C. Luo, L. M. C. Janssen, J. Farago, J. Baschnagel
Summary: The study investigates the structural relaxation of a binary Voronoi mixture using molecular dynamics simulations and mode-coupling theory, finding no significant qualitative differences compared to similar analyses on simple liquids with pairwise interactions. The analysis suggests that it is possible to predict microscopic dynamic properties of the system based on static structural correlations, even though many-body interactions are involved.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Physics, Fluids & Plasmas
I. Kriuchevskyi, J. P. Wittmer, H. Meyer, O. Benzerara, J. Baschnagel
Proceedings Paper
Crystallography
P. C. Montgomery, P. Chapuis, A. Leong-Ho, F. Anstotz, A. Rubin, J. Baschnagel, C. Gauthier, G. Reiter, G. B. McKenna
INERA WORKSHOP 2016: MEMBRANE AND LIQUID CRYSTAL NANOSTRUCTURES (MELINA 2016)
(2017)
