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Title: Thermal Transport through CTAB- and MTAB-Functionalized Gold Interfaces Using Molecular Dynamics Simulations
Thermal transport coefficients, notably the interfacial thermal conductance, were determined in planar and spherical gold interfaces functionalized with CTAB (cetyltrimethylammonium bromide) or MTAB (16-mercapto-hexadecyl-trimethylammonium bromide) using reverse non-equilibrium molecular dynamics (RNEMD) methods. The systems of interest included (111), (110), and (100) planar facets as well as nanospheres (r = 10 Å). The effect of metal polarizability was investigated through the implementation of the density-readjusted embedded atom model (DR-EAM), a polarizable metal potential. We find that conductance is higher in MTAB-capped interfaces, due in large part to the metal-to-ligand coupling provided by the Au-S bond. Alternatively, CTAB does not couple strongly with either the metal or the solvent, and it is largely a barrier to heat transfer, resulting in a much lower interfacial thermal conductance. Through analysis of physical contact between the ligand and the solvent, we find that there is significantly more overlap in the MTAB systems than the CTAB systems, mirroring the trends we observed in the conductance.  more » « less
Award ID(s):
1954648
PAR ID:
10613504
Author(s) / Creator(s):
;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Journal of Chemical Information and Modeling
Volume:
65
Issue:
2
ISSN:
1549-9596
Page Range / eLocation ID:
811 to 824
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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