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arXiv · 2211.08560

Development of a new quantum trajectory molecular dynamics framework

Pontus Svensson·Thomas Campbell·Frank Graziani·Zhandos Moldabekov·Ningyi Lyu·Victor S. Batista·Scott Richardson·Sam M. Vinko·Gianluca Gregori
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Abstract

An extension to the wave packet description of quantum plasmas is presented, where the wave packet can be elongated in arbitrary directions. A generalised Ewald summation is constructed for the wave packet models accounting for long-range Coulomb interactions and fermionic effects are approximated by purpose-built Pauli potentials, self-consistent with the wave packets used. We demonstrate its numerical implementation with good parallel support and close to linear scaling in particle number, used for comparisons with the more common wave packet employing isotropic states. Ground state and thermal properties are compared between the models with differences occurring primarily in the electronic subsystem. Especially, the electrical conductivity of dense hydrogen is investigated where a 15% increase in DC conductivity can be seen in our wave packet model compared to other models.

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Pontus Svensson, Thomas Campbell, Frank Graziani, Zhandos Moldabekov, Ningyi Lyu, Victor S. Batista, Scott Richardson, Sam M. Vinko, Gianluca Gregori. 2022-11-15. Development of a new quantum trajectory molecular dynamics framework. https://doi.org/10.1098/rsta.2022.0325

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