Article
Visible Absorption Spectroscopy and Structure of Cyanine Dimers in Aqueous Solution: An Experiment for Physical Chemistry
Purchase the full-text
- PDF/HTML,
figures/images,
references and tables,
(where available)
Abstract
The shape of the visible absorption spectra for cyanine dyes in aqueous solution is concentration dependent. This property is attributed to the formation of dimers and higher aggregates in solution. The shape changes are typically manifested by a splitting of the absorption bands or the appearance of new bands. These spectral features arise from exciton coupling between the molecules in an aggregate. In this experiment, an iterative procedure for obtaining the dimer spectrum from the composite spectra of concentrated dye solutions is used. Simple exciton theory is used to obtain information about the structure of the dimer from its spectrum. The iterative procedure and the application of simple exciton theory are demonstrated using the visible absorption spectra of 1,1'-diethyl-2,2'-cyanine in aqueous solution at different concentrations. In this experiment, concepts in quantum theory and spectroscopy are illustrated. These include energy delocalization, excitons, transition moments, and oscillator strengths. Expanding the scope of analysis to include dye aggregation and exciton theory enhances the pedagogical value of studying the visible absorption spectra of conjugated dyes in the physical chemistry curriculum.
Keywords (Audience):
Upper-Division UndergraduateKeywords (Domain):
Laboratory InstructionKeywords (Pedagogy):
Hands-On Learning / ManipulativesKeywords (Subject):
Dyes / PigmentsCiting Articles
Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.
This article has been cited by 6 ACS Journal articles (5 most recent appear below).

Photophysical and Lasing Properties of Rhodamine 6G Confined in Polymeric Nanoparticles
Virginia Martín, Jorge Bañuelos, Eduardo Enciso, Íñigo López Arbeloa, Ángel Costela, and Inmaculada García-MorenoThe Journal of Physical Chemistry C2011 115 (10), 3926-3933Photophysical and Lasing Properties of Rhodamine 6G Confined in Polymeric Nanoparticles
Virginia Martín, Jorge Bañuelos, Eduardo Enciso, Íñigo López Arbeloa, Ángel Costela, and Inmaculada García-MorenoThe Journal of Physical Chemistry C2011 115 (10), 3926-3933The photophysics and laser action of rhodamine 6G (Rh6G) confined in polymeric nanoparticles, based on copolymers of methyl methacrylate and 2-hydroxyethyl methacrylate, are analyzed as a function of the dye concentration, as well as the composition and ...

The Particle Inside a Ring: A Two-Dimensional Quantum Problem Visualized by Scanning Tunneling Microscopy
Mark D. EllisonJournal of Chemical Education2008 85 (9), 1282The Particle Inside a Ring: A Two-Dimensional Quantum Problem Visualized by Scanning Tunneling Microscopy
Mark D. EllisonJournal of Chemical Education2008 85 (9), 1282The one-dimensional particle-in-a-box model used to introduce quantum mechanics to students suffers from a tenuous connection to a real physical system. This article presents a two-dimensional model, the particle confined within a ring, that directly ...

Modern Developments in the Physical Chemistry Laboratory
Samuel A. Abrash2007 973 (), 115-151Modern Developments in the Physical Chemistry Laboratory
Samuel A. Abrash2007 973 (), 115-151Developments in the physical chemistry laboratory since the publication of the germinal text by Schwenz and Moore (1) are categorized and reviewed. The categories examined include modern instrumentation, current topics in chemistry, integrated ...

Determination of Micellar Microenvironment of Pinacyanol by Visible Spectroscopy
Raimon Sabaté and Joan EstelrichThe Journal of Physical Chemistry B2003 107 (17), 4137-4142Determination of Micellar Microenvironment of Pinacyanol by Visible Spectroscopy
Raimon Sabaté and Joan EstelrichThe Journal of Physical Chemistry B2003 107 (17), 4137-4142The interaction of pinacyanol, a cationic cyanine dye (PIN), with Triton X-100, sodium dodecyl sulfate, and alkyltrimethylammonium bromide micelles was studied by visible spectrophotometry. PIN exists as a monomer and in aggregated form (dimers, trimers, ...

A Spectroscopy Study of the Interaction of Pinacyanol with n-dodecyltrimethylammonium Bromide Micelles
Raimon Sabaté, Montserrat Gallardo, Alfonso de la Maza, and Joan EstelrichLangmuir2001 17 (21), 6433-6437A Spectroscopy Study of the Interaction of Pinacyanol with n-dodecyltrimethylammonium Bromide Micelles
Raimon Sabaté, Montserrat Gallardo, Alfonso de la Maza, and Joan EstelrichLangmuir2001 17 (21), 6433-6437The interaction of pinacyanol, a cyanine dye (PIN), with n-dodecyltrimethylammonium bromide (DTAB) at micellar concentration range was studied by visible spectrophotometry. As PIN is present in aggregate and nonaggregate forms, we aimed to determine the ...
Tools
-
Add to Favorites
-
Download Citation
-
Email a Colleague -
Permalink
Order Reprints
Rights & Permissions
Citation Alerts
History
- Received: August 03, 2009
Cart

ACS
Network






