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Abstract— Samples of quinine sulfate or bisulfate from a number of vendors have been examined. The light absorptivity and fluorescence excitation spectra of quinine bisulfate prepared from six sources of hydrated quinine sulfate had satisfactory agreement with each other. The solid samples of quinine sulfate or bisulfate showed good agreement (2.2 per cent relative difference) in their fluorescence quantum yields but the one commercial solution of quinine sulfate was 20 per cent low. The relative fluorescence quantum yield of quinine sulfate was evaluated with excitation from 240 through 400 nm and was found to have no unexplainable deviations from a constant value. It is suggested that some of the conflicting results in the literature may be due to the common practice of using a different spectral bandwidth for absorbance measurements than that used for excitation.

Studies were made of solutions of 1-octanol and 1-butanol in n-decane using the infrared absorption of the first overtone of the O-H stretch vibrations of the monomer and selfassociation polymers. Evaluation was made on 1-octanol solutions from 5 to 100°, without making use of a priori self-association models. Evaluations were performed by three methods involving comparisons of: (I) the monomer absorbance and the total alcohol concention, (II) the monomer absorbance and the polymer absorbance, and (III) a combination of I and II. The following new assignments were made: (1) the end O-H of linear selfassociation polymers do not contribute significant absorbance at the monomer peak in the first overtone region; (2) the monomer molar absorptivity is constant with temperature;(3) the usual "dimer" peak at 1.528 µ cannot be due to a O-H • O-H dimer as its absorbance varies directly proportionally to that of the monomer (it is tentatively assigned to an alcohol-solvent interaction); (4) the remainder of the polymer absorption is assigned solely to tetramers; and (5) the tetramers give partially overlapping peaks which are due to O-H bonds in two different tetramers. Thermodynamic values indicate a linear and a cyclic tetramer. The linear with three bonds has a AH of -16.5 kcal/mole and the cyclic with four bonds has a AH of -20.3 kcal/mole. Thus within the limits of error, all O-H first overtone absorption is explained by assigning a monomer in equilibrium with two tetramers. This holds from 10-4 M to neat 1-octanol over a 95°t emperature range. Data from other workers for other alcohols in CCk are evaluated and found to be consistent with the present assignments. Much more self-association of alcohols was observed in n-decane than was observed in CCh. In particular, kinetic data involving alcohols are explained by the physical model described.N. Y" 1959.

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