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Dynamics of Bulk vs. Nanoscale WS_2: Local Strain and Charging Effects

R. D. Luttrell·S. Brown·J. Cao·J. L. Musfeldt·R. Rosentsveig·R. Tenne
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Abstract

We measured the infrared vibrational properties of bulk and nanoparticle WS$_2$ in order to investigate the structure-property relations in these novel materials. In addition to the symmetry-breaking effects of local strain, nanoparticle curvature modifies the local charging environment of the bulk material. Performing a charge analysis on the \emph{xy}-polarized E$_{1u}$ vibrational mode, we find an approximate 1.5:1 intralayer charge difference between the layered 2H material and inorganic fullerene-like (IF) nanoparticles. This effective charge difference may impact the solid-state lubrication properties of nanoscale metal dichalcogenides.

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R. D. Luttrell, S. Brown, J. Cao, J. L. Musfeldt, R. Rosentsveig, R. Tenne. 2006-01-05. Dynamics of Bulk vs. Nanoscale WS_2: Local Strain and Charging Effects. https://doi.org/10.1103/physrevb.73.035410

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