J*******3
发帖数: 1651 | 1 Got confused about two concepts:
input file, Matrix of supercell(coordinates) is needed, while when
calculating some properties, Monkhorst Pack is also needed. What is the
difference between them? or they refer to one thing, one is in real space,
the other one in reciprocal space?
Many thanks! |
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J*******3
发帖数: 1651 | 2 Got confused about two concepts:
input file, Matrix of supercell(coordinates) is needed, while when
calculating some properties, Monkhorst Pack is also needed. What is the
difference between them? or they refer to one thing, one is in real space,
the other one in reciprocal space?
Many thanks! |
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J*******3
发帖数: 1651 | 3 Probably it is my misunderstanding. when I read the manual, I got
impression that the matrix of supercell is the transpose of Monkhorst matrix
, is this correct? |
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g*********n
发帖数: 808 | 4 Thank you so much for the valuable guidance! that helps me a lot!
Another stupid question: k-points usually refer to Monkhorst-Pack M*M*M.
But what Mesh cutoff refers to? and what it would affect in the calculation?
基的选择有几种， 标准是啥？
想必您肯定有很多实战经验，如何才能入门？ 很是痛苦的问：-）
有何高招，请务必指教。 水深火热呵。 |
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j*********m
发帖数: 33 | 5
calculation?
Yes, Monkhorst-Pack is most common k point sampling method. I think you
need to read something before really doing... |
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J*******3
发帖数: 1651 | 6 Is there any correlation between them?
many thanks! |
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R**X
发帖数: 417 | 7 u mean k mesh...thats the place u sample the wavefunction and do integral |
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v****x
发帖数: 498 | 8
~~~~~~~~~~~~~~~~~~~~~~ this is the system you
want to model
~~~~~~~~~~~~~~~~this is for k-space sampling,
which is used for integration (actually summation)
, |
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J*******3
发帖数: 1651 | 9 Is there any correlation between them?
Many many thanks! |
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v****x
发帖数: 498 | 10 a large cell ---> small reciprocal cell
so for a large cell, we can use a small k-mesh to obtain a similar accuracy;
for example, when we calculate cubic diamond using the 1x1x1 conventional
cell,
we need a 5x5x5 M-P k-mesh, when we calculate the 5x5x5 supercell, the 1x1x1
K-mech is enough |
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J*******3
发帖数: 1651 | 12 Thank you so much!
BTW: I bet you must be an expert in DFT. Any recommending books for
beginner, which would help to be on the track earlier?
Tons of thanks to you! |
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J*******3
发帖数: 1651 | 13 Thank you so much!
BTW: I bet you must be an expert in DFT. Any recommending books for
beginner, which would help to be on the track earlier?
Tons of thanks to you! |
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v****x
发帖数: 498 | 14 ...
For the calculations itself, read the manual, and the references in the
manual |
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