Accession Number : ADA195816

Title :   Optical Nonlinearity in DNA Films.

Descriptive Note : Annual rept. Jun 87-Jul 88,

Corporate Author : ARIZONA STATE UNIV TEMPE DEPT OF PHYSICS

Personal Author(s) : Lindsay, S M

PDF Url : ADA195816

Report Date : 15 Jun 1988

Pagination or Media Count : 7

Abstract : Raman scattering, Brillouin scattering and optical harmonic generation are being used to probe the electronic properties of DNA. The conformation transitions, and physical properties such as stiffness, optical polarizability, and vibrational frequencies of the molecule in the solid state are found to be strongly dependent on the counter ion. We have examined the alkali metal salts of DNA, finding (for the monovalent counter ions) that the controlling parameter is the ion size. Properties are affected by the formation of bonds (possibly mediated by diffuse ion cloud interactions) between phosphate groups. We also find that the dynamics of the double helix are strongly influenced by the primary hydration shell at GHz frequencies. We have used Brillouin scattering to examine the dynamics of bound water, and Raman scattering to examine its structure. DNA films have unusual elasto-optic properties. Keywords: DNA; Optical properties; Phase transitions; Optical harmonic generation; Molecular biology. (KT)

Descriptors :   ALKALI METALS, BONDED JOINTS, CLOUDS, CONFORMITY, DEOXYRIBONUCLEIC ACIDS, DIFFUSION, DYNAMICS, ELECTRONICS, FILMS, FREQUENCY, HARMONIC GENERATORS, HYDRATION, ION ION INTERACTIONS, IONS, LIGHT SCATTERING, MOLECULAR BIOLOGY, NONLINEAR SYSTEMS, OPTICAL PROPERTIES, PHASE TRANSFORMATIONS, PHONONS, PHOSPHATES, PHYSICAL PROPERTIES, POLARIZATION, RAMAN SPECTRA, SALTS, SHELLS(STRUCTURAL FORMS), SIZES(DIMENSIONS), STIFFNESS, TRANSITIONS, VIBRATION, WATER

Subject Categories : Genetic Engineering and Molecular Biology

Distribution Statement : APPROVED FOR PUBLIC RELEASE