Accession Number : AD0704958

Title :   THE PHOTOCHEMISTRY AND OPTICAL ROTATORY DISPERSION OF PHOTOCHROMIC BIANTHRONE.

Descriptive Note : Final rept. 1 Jul 66-30 Jun 69,

Corporate Author : RENSSELAER POLYTECHNIC INST TROY N Y

Personal Author(s) : Richtol,H. H. ; Strong,R. L.

Report Date : APR 1970

Pagination or Media Count : 21

Abstract : An investigation has been performed on the photochromic behavior of bianthrone and some of its derivatives. The photochromic transients in benzene solution have been studied by flash photolysis from 20-55C. This state is produced via the singlet excited state and decays by first-order kinetics (k(1) = 3-11/sec at 25C), with an energy of activation of 14-15 kcal/mole. Triplet energy transfer experiments with biacetyl as triplet donor show that the triplet state of the bianthrones can be a precursor to the photochromic state through energy transfer. Permanent photolysis of the bianthrones to helianthrones and naphthodianthrones occurs through the singlet excited state. The photoproducts have transients which decay by second-order kinetics. 2-Carboxybianthrone was resolved and its ORD curve obtained, but unfortunately it had low rotations and high absorptivities. (Author)

Descriptors :   (*ANTHRACENES, *PHOTOCHEMICAL REACTIONS), PHOTOCHROMISM, MOLECULAR ROTATION, KETONES, PHOTOLYSIS, REACTION KINETICS

Subject Categories : Radiation and Nuclear Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE