Questions tagged [correlation-functions]
The correlation-functions tag has no usage guidance.
12
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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 ...
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0
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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
7
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1
answer
117
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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
5
votes
1
answer
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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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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,
$$D(z) ...
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9
votes
1
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249
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What is autocorrelation time?
I'm writing this code of molecular dynamics about a pseudo-ideal gas in a box. The task is integrating the EOM for every atoms for a time-step dt fixed with the leapfrog method and measure the total ...
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How to use the HNC approximation to find the change in grand potential
I am reading Hansen and MacDonald's Theory of Simple Liquids, and I am going through Integral Equation theories.
In section 4.3, they put forward the equation (4.3.14),
$${\small \Omega _{\phi} = \...
- 4,091
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257
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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-...
- 14.6k
9
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1
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149
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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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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 ...
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22
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1
answer
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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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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 ...
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