Kinetics of trans-cis isomerization in azobenzene dimers at an air-water interface

Kumar, Bharat; Suresh, K.A.

Please use this identifier to cite or link to this item: http://hdl.handle.net/2289/3898

Full metadata record

DC Field	Value	Language
dc.contributor.author	Kumar, Bharat	-
dc.contributor.author	Suresh, K.A.	-
dc.date.accessioned	2010-01-20T11:41:19Z	-
dc.date.available	2010-01-20T11:41:19Z	-
dc.date.issued	2009-08-03	-
dc.identifier.citation	Physical Review E, 2009, Vol.80, p021601	en
dc.identifier.issn	1539-3755-P	-
dc.identifier.issn	1550-2376-E	-
dc.identifier.uri	http://hdl.handle.net/2289/3898	-
dc.description	Open Access	en
dc.description.abstract	We have studied the kinetics of trans to cis isomerization under the illumination of ultraviolet light, in the Langmuir monolayer of mesogenic azobenzene dimer, bis-[5-(4[prime]-n-dodecyloxy benzoyloxy)-2-(4[double-prime]-methylphenylazo)phenyl] adipate, at an air-water interface. We find that the trans to cis isomerization reaction of the molecules in the monolayer shows deviation from the first-order kinetics unlike those reported on Langmuir monolayers of azobenzene molecules. We attribute the deviation from first-order kinetics to the simultaneous photoisomerization of trans isomers to form cis isomers and the reverse thermal isomerization of cis isomers to form trans isomers. Our analysis of the rate of change of mole fraction of trans isomers to form cis isomers indicates a first-order kinetics for trans to cis photoisomerization reaction and a second-order kinetics for cis to trans thermal isomerization reaction. This second-order kinetics mechanism is similar to the Lindemann-Hinshelwood mechanism for the unimolecular reactions at low concentration of reactants. The formation of the activated cis isomer by collisions is a slow process as compared to the decay of the activated cis isomer to trans isomer in the liquid expanded phase. This results in the second-order kinetics for the thermal isomerization of cis isomers.	en
dc.language.iso	en	en
dc.publisher	The American Physical Society	en
dc.relation.uri	http://dx.doi.org/10.1103/PhysRevE.80.021601	en
dc.rights	2009 by the American Physical Society	en
dc.subject	isomerisation	en
dc.subject	monolayers	en
dc.subject	organic compounds	en
dc.subject	photochemistry	en
dc.subject	reaction kinetics	en
dc.title	Kinetics of trans-cis isomerization in azobenzene dimers at an air-water interface	en
dc.type	Article	en
Appears in Collections:	Research Papers (SCM)

Files in This Item:

File	Description	Size	Format
2009_PhysRevE_v80_p021601.pdf	Open Access	166.16 kB	Adobe PDF	View/Open

Show simple item record