| Silver Tetracyanoquinodimethane (AgTCNQ) is an organometallic semiconducting compound which has the ability to "switch" between two distinct states. These two states have different electrical and optical properties, thus making this compound potentially useful as a memory storage material.;Using Raman Spectroscopy, these two states have distinct vibrational peaks, pointing toward the possibility of using Raman as a tool for discerning between the two states of AgTCNQ. However, Raman peaks of bulk AgTCNQ samples are typically very weak and the substrate runs the risk of laser induced degradation.;In this research, we explore new ways of preparing AgTCNQ. First, Ag particles with controllable sizes (25 Angstroms-500 nm) are prepared by chemical precipitation. This is done in an aqueous micellar environment using SDS (sodium dodecyl sulfate) as surfactant and also in a heptane inverse micellar system using the AOT (sodium dioctyl sulfosuccinate) surfactant.;AgTCNQ colloidal particles formed from these Ag particles have been found to exhibit very intense Raman signals even under low exciting laser powers. This is due to an enhancement of Raman vibrational modes, and the spectroscopic technique is known as surface-enhanced Raman spectroscopy (SERS).;We present Raman spectra of AgTCNQ colloidal systems, as well as comprehensive characterization of Ag and AgTCNQ colloids. |
