Knowledge Bank

Infrared absorption by the $\nu 3$ fundamentals of $CO2$ and $N2O$ in dilute solution in MBBA has been measured over the temperature range $20\circ$ to $60\circ C$. Band-shape analyses of the spectral profile show that the torque acting on the solute molecule varies rapidly through the nematic $\to$ isotropic phase transition. These results demonstrate that small molecules can serve as molecular probes which are sensitive to solvent phase changes and suggest the application of this method to the study of membrane structure.