Detail of "1211-40-1"

Reference

Modified Carbon Surfaces as "Organic Electrodes" That Exhibit Conductance Switching

Modified Carbon Surfaces as "Organic Electrodes" That Exhibit Conductance Switching. Solak, Ali Osman; Eichorst, Laura R.; Clark, William J.; McCreery, Richard L. (Department of Chemistry, Ohio State University, Columbus, OH 43210-1185, USA). Analytical Chemistry, 75(2), 296-305 (English) 2003 American Chemical Society. CODEN: ANCHAM. ISSN: 0003-2700. DOCUMENT TYPE: Journal CA Section: 72 (Electrochemistry) Section cross-reference(s): 22, 67, 76 Glassy C (GC) surfaces modified with monolayers of biphenyl and nitrobiphenyl mols. were examd. as voltammetric electrodes for ferrocene, benzoquinone, and tetracyanoquinodimethane electrochem.Some commonly used reagents like 488735-96-2 and 1211-40-1 are used in this experiment. in MeCN. The modified electrodes exhibited slower electron transfer than unmodified GC, by factors that varied with the monolayer and redox system. However, after a neg. potential excursion to ~-2.0 V vs. Ag+/Ag, the modified electrodes exhibited much faster electron-transfer kinetics, approaching those obsd. on unmodified GC. The effect is attributed to an apparently irreversible structural change in the biphenyl or nitrobiphenyl monolayer, which increases the rate of electron tunneling. The transition to the ON state is assocd. with electron injection into the monolayer similar to that obsd. in previous spectroscopic studies and causes a significant decrease in the calcd. HOMO-LUMO gap for the monolayer mol. Once the monolayer is switched ON, it supports rapid electron exchange with outer-sphere redox systems, but not with dopamine, which requires adsorption to the GC surface. The increase in electron-transfer rate with electron injection is consistent with an increase in electron tunneling rate through the monolayer, caused by a significant decrease in tunneling barrier height. The ON electrode can reduce biphenyl- or nitrobiphenyldiazonium reagent in soln. to permit formation of a 2nd modification layer of biphenyl or nitrobiphenyl mols. This double derivatization procedure was used to prep. tetraphenyl- and nitrotetraphenyl-modified electrodes, which exhibit significantly slower electron transfer than their biphenyl and nitrobiphenyl counterparts. A switching electrode may useful properties for electroanal. applications and possibly in electrocatalysis. The ON state represents an org. electrode in which electron transfer occurs at an interface between an org. conductor and a soln. rather than an interface between a soln. and a metal or C electrode. .

Intensity and frequency vibrational spectroscopy: nonlinear optical response of polyconjugated materials

Some chemicals with cas registry numbers like 1211-40-1 and 6203-18-5 are also used. Intensity and frequency vibrational spectroscopy: nonlinear optical response of polyconjugated materials. Del Zoppo, Mirella; Zerbi, Giuseppe (Dipartimento di Chimica Industriale Politecnico di Milano, Milan 20133, Italy). GNSR 2001, State of Art and Future Development in Raman Spectroscopy and Related Techniques, Reggio Calabria, Italy, May 14-16, 2001, Meeting Date 2001, 68-77. Edited by: Messina, Giacomo; Santangelo, Saveria. IOS Press: Amsterdam, Neth. ISBN: 1-58603-262-3(English) 2002. CODEN: 69EKX8. DOCUMENT TYPE: Conference CA Section: 22 (Physical Organic Chemistry) Section cross-reference(s): 73 The authors wish to show the importance of vibrational spectroscopy in the study of the mol. electronic properties of polyconjugated mols. in particular it is possible from the knowledge of vibrational abs. intensities (IR, Raman and hyperRaman) to obtain the vibrational contribution to nonlinear optical responses. This contribution, in the case of polyconjugated systems, is very large (of the same order of magnitude or even larger than the electronic one) and in many instances it correlates well with its electronic counterpart. Also new criteria to relate intensity patterns to mol. structure of polyconjugated systems are discussed. .