Questions tagged [monte-carlo]
For questions related to Monte Carlo methods, which solve deterministic numerical problems via a probabilistic sampling approach.
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Metropolis algorithm reduces energy in molecular simulation, but does not decrease euclidean distance
I am using an open source python package openmmtools to run a simple molecular simulation problem using the metropolis algorithm.
I first load a default system of particles (alanine-dipeptide in ...
9
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2answers
92 views
Starting configuration for a molecular simulation
When doing a computer simulation, what’s the best way to prepare a starting configuration to avoid biasing your results?
The book Computer Simulation of Liquids suggests putting the molecules on an ...
9
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1answer
452 views
Why is specific heat not zero at absolute zero?
In this old paper on Monte Carlo simulations of Lennard-Jones solid, specific heat behaviour (both $c_p$ and $c_v$) have been reported. As you can see from the picture below, both $c_p$ and $c_v$ goes ...
12
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1answer
199 views
Is there a more efficient hard sphere packing algorithm?
I am trying to pack hard-spheres in a unit cubical box, such that these spheres cannot overlap on each other. This is being done in Python.
I am given some packing fraction ...
12
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1answer
398 views
Are there examples of ab initio predictions on small molecules without the “major approximations”?
In most textbooks the precise Schrödinger euqation of a molecule is given (and the "beautiful thing" stops here), then born oppenheimer approximation is made, then layers of other ...
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2answers
336 views
Classical Monte Carlo vs. Molecular Dynamics
Both Classical Monte Carlo (MC) and Classical Molecular Dynamics (MD) simulations are used to perform simulations of ensembles of molecules. These MC calculations are calculating thermodynamic ...
10
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1answer
123 views
How does one compute the boiling point of a liquid made of a particular molecule?
This question is in relation to Anomalous boiling point of "iso-" alkanes on Chemistry SE.
I want to compute the boiling point of the different isomers of an n-carbon alkane to check what ...
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0answers
97 views
Coupling between 1st and 2nd order phase transitions?
I am seeking some models or references on how to couple, or what to take into consideration, while coupling first-order phase transitions (for magnetic systems) and second-order phase transitions, in ...
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0answers
149 views
Why does the Wolff algorithm slow down in a 4-body Ising model?
In the paper that introduced "Self-learning MC" (an ML-inspired MC technique, as I understand) the authors consider a many-body Ising model as an example to show the efficiency of their ...
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3answers
195 views
What are the types of Quantum Monte Carlo?
Similar to:
What are the types of SCF?
What are the types of MCSCF?
What are the types of ab initio Molecular Dynamics?
What are the types of pseudopotentials?
What are the types of DFT?
What are the ...
18
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1answer
89 views
How can very small lattices be sufficient for Quantum Monte Carlo simulations?
Quantum Monte Carlo simulations are often performed with very modest lattice sizes (such as [e-print], $64$ sites), due to their computational cost increasing exponentially with the system volume; ...
12
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2answers
151 views
Autocorrelation function problem in Monte Carlo simulation of 2D Ising model
Currently, I did a Monte Carlo simulation with the local update and Wolff cluster updated in 2D classical Ising model. I use the autocorrelation function to compare 2 different algorithm in critical ...
12
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2answers
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In Monte Carlo: does nonequilibrium imply stationary state?
I'm currently responding to referees about a manuscript on the dynamics of the Ising model. I have been using the term nonequilibrium to refer to any state that is not characteristic of the ...
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2answers
108 views
How to simulate atomic scattering from solid walls at finite temperature for a particles in a box simulation?
I'm not sure if this will be considered on-topic, let's see what happens. I've asked this previously in Physics SE and it was closed as needing focus. It is now past 30 days and too late to consider ...
13
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1answer
76 views
What are the modelling techniques that can be used for simulating microstructure evolution in materials?
I am aware that the Potts Model can be used to simulate grain growth, and that Phase Field Models have also been very successful. What are the advantages and limitations of these models? What are the ...
15
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1answer
124 views
What is the definition of ergodicity in Monte Carlo?
I've been writing a manuscript about the breakdown of ergodicity in single spin flip Metropolis algorithm Monte Carlo arXiv:2001.09268.
The definition I have been using is: a Markov process is ...
