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In molecular mechanics, how are van der Waals forces modelled?
In terms of energy, how are van der Waals forces modelled (are there formulas/laws that govern these)?
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20
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When using the "even tempered method" for augmenting basis sets, what justification is there for the numerical factor which is used?
Diffuse functions are often added to basis sets using "even-tempered" exponents, or sometimes I have heard the phrase "even tempering".
In this paper by Jacek Koput, the author says "the customary ...
21
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2
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Why were no correlation consistent basis sets for potassium contracted for a non-relativistic Hamiltonian?
On basis set exchange, the only correlation consistent (cc) basis sets for potassium, are relativistic (labelled by X2C). Very recently (I consider 2017 quite recent, because most Dunning basis sets ...
55
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What is the closest thing we have to "the" universal density functional?
It is understood that finding "the" universal functional is an NP-complete problem. However, progressively better functionals have been constructed decade after decade and fitted to more and more ...
57
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Is there a database where we can find previously determined geometries of materials?
For small molecules, NIST has a database of experimentally determined geometries here, and ab initio geometries here. I wonder if there is something similar for materials?