PHYS 386 |
| The properties of the triplet state of acridine 9-carboxylic acid (9-ACA) in aqueous solutions were determined using photoacoustic calorimetry and photothermal beam deflection. The triplet state decays to the ground state with the rate constant of 5.8x103s-1 and 3.2x106s-1 at pH 7.0 and pH 3.0, respectively. The triplet state quantum yield was measured to be 0.32 „b 0.04 at neutral pH and somewhat smaller 0.20 „b 0.04 at acidic pH. Formation of the triplet state is associated with a volume decrease of - 5.0 „b 2.7 mL/mol at pH 7.0 and - 13.0 „b 2.5 mL/mol at pH 3.0. The observed data are discussed in term of the acid-base equilibria involved in the ground and excited state. |
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PHYS Poster Session - General Experiment
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Division of Physical Chemistry |