ISSN:
0006-3525
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
We have measured the refractive indices of highly crystalline Li- and Na-DNA wet-spun films as a function of their water content using an immersion technique. We calculated the molecular polarizabilities of a DNA base pair using the Lorentz-Lorenz relation for anisotropic materials, the measured water contents, and densities corrected for void formation. For Li-DNA, the polarizabilities are independent of the relative humidity, whereas for Na-DNA, there are large changes at the A-B transition and also at low humidities. The average polarizability of A-Na-DNA is in agreement with that calculated from refractive index increments and also as calculated by a simple addition of bond polarizabilities, whereas the values for Li- and B-Na-DNA are about 30% larger than the calculated values. We propose that these anomalous values are due to nonlinear polarizabilities of the phosphate group.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bip.360260310
