Questions tagged [correlation-functions]
The correlation-functions tag has no usage guidance.
13
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How exactly does one compute the vibrational density of states from the output of a molecular dynamics simulation?
There are many things that can be done with the output of a molecular dynamics simulation, but one of the more powerful things is the ability to compute the vibrational density of states (or the ...
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12
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0
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Correlation Functions in the Cluster Variation Method [closed]
I've been referring to Dr Mohri's paper [DOI: 10.1007/s11837-013-0738-5] for the cluster variation method (CVM). I wish to calculate the configurational entropy of a binary FCC system.
Cluster ...
- 5,125
9
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1
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What is autocorrelation time?
I'm writing this code of molecular dynamics about a pseudo-ideal gas in a box. The task is integrating the EOM for every atoms for a time-step dt fixed with the leapfrog method and measure the total ...
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9
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Derivation on correlation function and response functions in polymer physics
I am reading Introduction to Polymer Physics by Doi and I am having trouble understanding a derivation by him on the concentration fluctuations in polymer solutions. I have outlined his method and ...
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How to use the HNC approximation to find the change in grand potential
I am reading Hansen and MacDonald's Theory of Simple Liquids, and I am going through Integral Equation theories.
In section 4.3, they put forward the equation (4.3.14),
$${\small \Omega _{\phi} = \...
- 4,141
7
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1
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VdW-D3 correction with HSE06 functional in VASP
I am trying to account for Vander waals correction in VASP. Now doing this for PBE is easy all one has to do is set IVDW=11 but the VASP webpage for DFT-D3 says ...
- 629
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Which Exchange Correlational Functional should be chosen for calculation of optical properties in VASP using LOPTICS tag?
I am planning on calculating optical properties mainly dielectric constant using LOPTICS tag in VASP. Now for my electronic calculations I have been using HSE06 mainly because of higher accuracy of ...
- 629
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161
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Diffusion coefficient as a function of distance from the position autocorrelation function [closed]
I am trying to understand if my idea for the computation of diffusion coefficient as a function of distance is right or not. So, the diffusion coefficient as a function of distance is given by,
$$D(z) ...
- 911
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325
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What's the pair correlation function? What information does it contain? [closed]
This question is related to this VASP tutorial, in which the pair correlation function (or radial distribution function: RDF) is utilized to justify whether the solid silicon is melt by AIMD (ab-...
- 14.8k
7
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Deriving relations for a hard sphere phase diagram [closed]
In Torquato's book "Random Heterogeneous Materials", he has written:
$$\frac{p}{\rho kT} = 1+2^{d-1}\eta g_2 (D^{+})\tag{1}$$
where $g_2(D^+)$ is the contact value from the right-side of the ...
- 4,141
5
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Programming auto-correlation function calculation
I have a set of data (heat flow) values in x, y and z directions for which I have to calculate the auto-correlation function to get the thermal conductivity. I have written a small Fortran90 code but ...
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2D Infrared spectroscopy for bulk systems using molecular dynamics
There are some questions and answers (1,2) on this site regarding simple infrared and vibrational density of states calculations with molecular dynamics and there any simple algorithmic descriptions ...
- 2,252
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Effect of trajectory length and resolution on the Residence Time
I have tried to calculate Residence time using the residence time auto-correlation function defined as
$$R(t) = \frac{\langle h(0)h(t)\rangle}{\langle h(0)h(0)\rangle}$$
In the calculation, I have ...
- 121