The virial stress tensor-based instantaneous heat flux, which is used by LAMMPS, is only valid for the small subset of simulations that contain only pairwise interactions. For systems that contain many-body interactions using 3-or 4-body potentials, a more complete derivation is required. We have created a software patch to LAMMPS that implements the correct heat flux calculation approach for 3-and 4body potentials, based on the derivation by Torii et al. (J. Chem. Phys. 2008, 128, 044504) Using two example systems, the error in the uncorrected code for many-body potential heat flux is shown to be significant and reaches nearly 100% of the manybody potential heat flux for the systems we studied; hence, the error of the total heat flux calculation is proportional to the fraction of the total heat flux transferred through the many-body potentials. This error may have consequences for thermal conductivities calculated using the Green−Kubo method or any NEMD method that uses the instantaneous heat flux. We recommend that all researchers using LAMMPS for heat flux calculations where significant heat is transferred via the many-body potentials adopt the corrected code.
Metal-organic frameworks (MOFs), along with other novel adsorbents, are frequently proposed as candidate materials to selectively adsorb CO2 for carbon capture processes. However, adsorbents designed to strongly bind CO2 nearly...
Adsorption-based
capture of CO2 from flue gas and from
air requires materials that have a high affinity for CO2 and can resist water molecules that competitively bind to adsorption
sites. Here, we present a core–shell metal–organic framework
(MOF) design strategy where the core MOF is designed to selectively
adsorb CO2, and the shell MOF is designed to block H2O diffusion into the core. To implement and test this strategy,
we used the zirconium (Zr)-based UiO MOF platform because of its relative
structural rigidity and chemical stability. Previously reported computational
screening results were used to select optimal core and shell MOF compositions
from a basis set of possible building blocks, and the target core–shell
MOFs were prepared. Their compositions and structures were characterized
using scanning electron microscopy, transmission electron microscopy,
and powder X-ray diffraction. Multigas (CO2, N2, and H2O) sorption data were collected both for the core–shell
MOFs and for the core and shell MOFs individually. These data were
compared to determine whether the core–shell MOF architecture
improved the CO2 capture performance under humid conditions.
The combination of experimental and computational results demonstrated
that adding a shell layer with high CO2/H2O
diffusion selectivity can significantly reduce the effect of water
on CO2 uptake.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.