**Contributions of force field interaction forms to Green-Kubo viscosity
integral in n-alkane case**

N Kondratyuk, JOURNAL OF CHEMICAL PHYSICS, 151, 074502 (2019).

DOI: 10.1063/1.5103265

Decades of molecular simulation history proved that the Green-Kubo
method for shear viscosity converges without any problems in atomic and
simple molecular liquids, unlike liquids with high values of viscosity.
In the case of highly viscous liquids, the time decomposition method was
developed in 2015 by Maginn and co-authors **Y. Zhang, A. Otani, and E.
J. Maginn, J. Chem. Theory Comput. 11, 3537-3546 (2015)** which allows us
to improve the convergence of the Green-Kubo integral. In this paper,
the contributions of intramolecular and intermolecular force field parts
to the viscosity integral are discovered to gain the understanding of
the Green-Kubo method. The n-alkanes from n-ethane to n-pentane at 330 K
in the optimized potentials for liquid simulations-all atom force field
are used as reference models. The dependencies of these contributions
and decay times of the corresponding correlation functions on the chain
length are observed. The nonequilibrium simulations are carried out to
verify the Green-Kubo results. The obtained values of viscosity are
compared with experimental data.

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