The thermal conductivity can be calculated with MD or DFT(Boltzman transport equation, etc.). Does MD simulation includes isotopic effect on themral conductivity?
When you say MD, that is a method which is always placed atop another method, so there is MD using molecular mechanics (MM, i.e. force fields), semiempiric methods or full QM treatment, which would be DFT, HF or even more advanced. Therefore an MD takes into account isotopic effects when the underlying method accounts for it.
So if you put MD atop of DFT, you probably would end up with a better result than when you use a determination equation on a stiff single-point DFT since that would be essentially a 0K calculation. Please be aware that DFT-MD can be quite expensive calculations.
For an molecular dynamics simulation one has to specify a particle mass. Therefore isotopic effects due to the effect of mass on velocity are accounted for.
There are, however, some caveats: (1) For the determination of thermal conductivities of mixtures of nuclidic species one needs a MD program that can handle mixtures. If the MD technique is NEMD and the sample a liquid or gas, the temperature gradient will cause a concentration gradient, and this has an influence on the evaluation procedure. (2) Simulations get difficult when quantum effects come into play. Hydrogen and helium, for instance, require special precautions.
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