Influence of the Solvent on the Thermal Back Reaction of One Spiropyran

Autor/in	Piard, Jonathan
Titel	Influence of the Solvent on the Thermal Back Reaction of One Spiropyran
Quelle	In: Journal of Chemical Education, 91 (2014) 12, S.2105-2111 (7 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0021-9584
DOI	10.1021/ed4005003
Schlagwörter	Chemistry; Physics; Kinetics; Science Experiments; Optics; Undergraduate Students; College Science; Spectroscopy; Laboratory Experiments + Suchen Sie Ihr Suchwort? Chemie; Physik; Kinetik; Optik; Spektroskopie; Laboratory work; Laborarbeit
Abstract	The solvent influence on the absorption spectra and the kinetics of the back reaction of the 1',3'-dihydro-1',3',3'-trimethyl-6-nitrospiro(2H-1-benzopyran-2,2'-2H-indole) (6-NO2-BIPS) has been investigated by means of temperature-controlled, UV-visible spectroscopic measurements. The back reaction process was proved to follow first-order kinetics for five different solvents (toluene, THF, acetonitrile, DMSO, and ethanol) at several temperatures. Kinetics parameters (E[subscript a], A, t, ?H#, ?S#, and ?G#) were extracted from absorbance decay profiles for all solvents, and a simple model based on solvation mechanism was proposed in good agreement with experimental results. Such a photochromic compound also exhibits strong solvatochromism in its merocyanine form. All these experiments were performed to illustrate solvent effects on kinetic processes and optical properties for students with an undergraduate physical chemistry theoretical background. All the experiments described could be performed in a physical chemistry undergraduate laboratory. (As Provided).
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Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2017/4/10