ABSTRACT
This chapter demonstrates the use of the optical Kerr effect (OKE) to provide quantitative structural information on very short double helical deoxyribonucleic acid (DNA) fragments and a yeast transfer ribonucleic acids. In both the OKE and transient electric birefringence experiments, birefringence is transiently induced in an aqueous solution by an externally applied electric field. OKE was used to measure the rotational transport properties of B-DNA using the same sequences and buffers used by in the polarized and depolarized dynamic light scattering of W. Eimer and R. Pecora. The DNA arrives single-stranded in a lyophilized pellet contained in a small tube and must be resuspended and annealed. The optical signal was recorded in the same manner as in the OKE experiment. The birefringence arose from both the permanent and the induced dipole moments, whereas only the induced dipole moment contributed in the OKE experiments. The signal strength in the OKE experiment depends exclusively on an induced moment via the molecular polarizability.
