Molecular Adsorbate in PS-SERES

B) = 532.0 nm, and, C) = 632.8 nm. For each both the wavelength location of the excitation (solid line) and the scattering (dashed line) are mariced. The overlaid line rqtiesents the bin-averaged values of the LSPR Xn and EF. Bin widths are 24 nm (6A), 16 nm (6B), and 16 nm (6C). Reproduced with permission from J. Phys. Chem. B 2003, ASAP, 03/29/2003. Copyright 2003 Am. Chem. Soc. 

In each of the cases presented, the PS-SERES follow a pattern where correlation of the substrate LSPR allows achievement of high S/N ratio SER spectra. It is important to note that in all PS-SERE spectra collected to date, including those presented herein, a small percentage of measured EFs fall significantly above (viz., two to four times) the average EF values. While this occurrence is repeatable from sample to sample and for different excitation wavelengths, adsorbates, vibrational modes, and electronic resonance conditions, its cause is currently unknown and under active investigation. 

This chapter highlights representative research accomplishments in the area of fundamental and applied studies of the tunable LSPR. Specific applications in the Van Duyne laboratory include exploitation of the LSPR as a signal transduction mechanism for sensing applications and optimization of SERS signals. The optical properties of metallic nanostructures will find future application in the areas of dichroic filters. 

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