Reflection−absorption infrared (RAIR) and surface-enhanced Raman scattering (SERS) spectroscopy were used to determine the orientation of the bulk and interface of a polymer thin film formed by atactic poly(methyl methacrylate) (a-PMMA) which was dip-coated onto a novel dual-sided substrate. The novel substrate with silver particles deposited on both sides of a glass slide by silver mirror reaction had two sides with different roughness and reflectivity. The top side (rough) and the bottom side (smooth) were suited for the SERS and RAIR analyses, respectively. The experimental results suggested that the molecular chain axis of bulk a-PMMA tended to parallel orientation to the silver substrate a little. However, the polymers at interface obviously oriented parallel to the substrate. A conformation transition of ester groups of a-PMMA after annealing at high temperature was confirmed using SERS and RAIR techniques.

The time correlation functions for a Gaussian wave-packet preparation of the dissipative harmonic oscillator evolving from three initial conditions for the heat bath are calculated and compared with each other for Ohmic heat baths. The three initial distributions for the bath are the factorized, partially factorized, and unfactorized distributions. Explicit analytical formulas are derived and then used to study the effect of the three initial distributions on the subsequent dynamics. We find that the transient behavior does not depend sensitively on the initial condition as long as the initial Gaussian wave function of the system is centered at the equilibrium point. Differences become noticeable as the center of the wave packet is significantly shifted from the equilibrium point. These observations justify to some extent the prevalent use of factorized initial conditions for studying real time quantum dynamics in dissipative systems. The total energy in the system is also calculated for the three initial states and its relation to features in the decay is pointed out.