William Hinsberg, Joy Cheng, et al.
SPIE Advanced Lithography 2010
The thermochromic behavior of a number of dialkyl-substituted polysilanes has been studied in some detail. The formation of a long wavelength-absorbing species in solution at low temperatures is dependent on the polymer structure. Evidence for polymer aggregation has been found in solutions as dilute as 10-5M (based on the monomer unit). Fluorescence emission studies at very low concentrations (<10-6M) suggest that single-molecule events can result in the observed thermochromic changes. We have obtained no evidence for the proposed coil-to-rod transition at low temperature by either light or neutron scattering; indeed the scattering studies seem to suggest that the polymer coil dimensions actually shrink slightly prior to the onset of aggregation. It is proposed that the thermochromism observed for many dialkyl polysilanes in solution is initiated by the formation of extended segments within a polymer chain which are long enough to stabilize intra- and intersegmental interactions. In extremely dilute solutions this interaction results in a shrinkage of a single polymer chain; at higher concentrations the interaction results in aggregation. © 1991 Plenum Publishing Corporation.
William Hinsberg, Joy Cheng, et al.
SPIE Advanced Lithography 2010
Peter J. Price
Surface Science
Oliver Schilter, Alain Vaucher, et al.
Digital Discovery
A.B. McLean, R.H. Williams
Journal of Physics C: Solid State Physics