Dynamical solvation effects on the cis-trans isomerization reaction: photoisomerization of merocyanine 540 in polar solvents

Onganer, Yavuz; Yin, Mary; Bessire, David R.; Quitevis, Edward L.

doi:10.1021/j100112a040

Cited by 65 publications

(80 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…No trends in the behavior of k iso and E a were found for the spirooxazines in nitriles. The different behavior in two series of solvents is not unexpected as it has been observed for the isomerization of related compounds [31]. Moreover, that the solvent effects are much less in nitrile solution than in alcohol solution can be related to the lower intensity of the solvation interactions expected for the nitriles.…”

Section: 2supporting

confidence: 60%

Thermal Back-Isomerization of Spirocyclic Naphtho-oxazine and Phenanthro-oxazine Derivatives in Alcohols, Nitriles, and Poly(alkyl methacrylates)

Völker

O'Connell

Negri

et al. 2001

HCA

View full text Add to dashboard Cite

Dedicated to Professor AndreÂ M. Braun on the occasion of his 60th birthdayThe thermal back-isomerization of spiro[indole-naphtho-oxazine] 1 and spiro[indole-phenanthro-oxazine] 2 was studied in a series of primary alcohols, nitriles, and poly(methylmethacrylate), poly(ethylmethacrylate), and poly(isobutyl methacrylate) films by laser-flash photolysis in the temperature range of 0 ± 708. The decay is monoexponential in fluid solution, but deviates strongly from this behavior in polymeric environments even above the glass transition temperature of the polymers (Tg). In liquids, a very small solvent effect is observed on the isomerization rate constants (k iso ) for 1, which is attributed mostly to the solvent viscosity h. The values of k iso for 2 show influence of solvent viscosity and polarity, which were studied by application of a semiempirical relationship that accounts for non-Markovian processes. The decay kinetics in polymers was described by a Gaussian distribution of the activation energy and by a kinetic model that takes into account the simultaneous relaxation of the probe and the environment. For 1 and 2, the rate constant at the center of the Gaussian distribution is very similar to the first-order rate constant in nonpolar solvents. The Gaussian width of the distribution (s) decreases with temperature and is very similar in all polymers under Tg, and, above Tg, s decreases more abruptly. We make comparisons of the parameters derived from analysis of both 1 and 2 in polymers, as well as of their behaviors in solution and in polymers.

show abstract

Section: 2supporting

confidence: 60%

Thermal Back-Isomerization of Spirocyclic Naphtho-oxazine and Phenanthro-oxazine Derivatives in Alcohols, Nitriles, and Poly(alkyl methacrylates)

Völker

O'Connell

Negri

et al. 2001

HCA

View full text Add to dashboard Cite

show abstract

“…1,5 Recently, however, experimental results that could not be described by either the Smoluchowski or the Kramers formula in a self-consistent manner have begun to appear in the literature. [5][6][7][8] In these experiments the rate is typically described by power laws of the form (1/η) R , where the exponent R is a positive fraction less than 1. The derivative of the rate with respect to 1/η varies as (1/η) R-1 which goes to infinity as η f ∞.…”

Section: Power Law Behaviormentioning

confidence: 99%

“…The first one is to determine whether the photoisomerization rate of MC 540 in the alcohol solvents can be described by the ZH model. After a description of the experimental results and analysis of Onganer et al, 8 a detailed comparison of the experimental data with the ZH model and the parameters of that model can be determined. It develops that the fitting parameters are such that the experimental data are near the critical point of the ZH model.…”

Section: Objectivesmentioning

confidence: 99%

Universality in Isomerization Reactions in Polar Solvents

et al. 1996

Self Cite

View full text Add to dashboard Cite

Recently it has been shown by Singh and Robinson (SR) that universality and scaling occur in the van der Zwan-Hynes (ZH) model of dipole isomerization reactions near a critical point. This advance in the understanding of chemical reactions was accomplished through the discovery of an analogy of this critical point with the one in the van der Waals equation of state for an imperfect gas. In the present paper, the experimental data of Onganer et al. on the cis-trans photoisomerization of merocyanine 540 in n-alkyl alcohol and n-alkanenitrile solvents, as a function of the solvent shear viscosity and temperature, is analyzed in terms of the ZH model. This model, based on the Grote-Hynes theory, uses a non-Markovian solvent friction characterized by a reactant-solvent coupling strength parameter , the solvent inertial response time r, and the solvent frictional or viscous response time x. It is found that the photoisomerization data with alcohol solvents fit the ZH model reasonably well, and the fitted parameters , r, and x are found to lie in the regime near the singularity or the critical point of the ZH model. Utilizing the results of the SR study mentioned above, the experimental isomerization rate is shown to obey a universal scaling relation involving the two scaled variables, y ) (1 -)r and z ) (1 -)x 2/3 , of the ZH theory in the critical regime. A fractional power law dependence of rate on the inverse of viscosity arises naturally from the theory. The two-variable experimental scaling function is shown to agree with the theoretical scaling function of the ZH model, thus demonstrating the existence of scaling and universality in these experimental data.

show abstract

“…Photoisomerization of olefins and polyenes such as stilbene and its analogues, 76 diphenylbutadienes 77-82 and carbocyanines [83][84][85][86][87][88][89][90][91][92] has been thoroughly investigated in organic solvents in the recent past. Figure 8 shows a schematic of the isomerization process for olefins and polyenes.…”

Section: Photoisomerization Studiesmentioning

confidence: 99%

“…The term, F(ζ) is a dynamical quantity that depends on solute-solvent frictional coupling. 91 The solute-solvent frictional effects and the viscosity dependence of the isomerization rates are usually compared to theoretical models for F(ζ). Even though ln(k nr ) vs 1/T plots are given in figure 10, the activation energies or barrier heights of the reaction cannot be estimated from such plots because of the expected influence of temperature on viscosity.…”

Section: Photoisomerization Studiesmentioning

confidence: 99%

The role of specific interactions on dynamical processes in a room temperature ionic liquid

Mali

2009

J Chem Sci

View full text Add to dashboard Cite

This article describes our ongoing efforts to comprehend the role of specific interactions on the dynamical processes such as rotational diffusion and photoisomerization in a typical room temperature ionic liquid. Rotational diffusion studies carried out with a pair of structurally similar non-dipolar solutes indicate that organic solutes do experience strong specific interactions even with the highly associative ionic liquids such that their rotation is hindered. Similar measurements carried out with a nonpolar and a dipolar solute in an ionic liquid and a conventional solvent reveal that even in ionic liquids, apart from the viscosity of the medium, the important parameters, which govern the solute rotation are the solvent-size and free volume in case of non-polar solutes, whereas for charged and dipolar solutes, it is the solute-solvent interaction strength. Photoisomerization studies dealing with a pair of carbocyanine derivatives have shed light on the influence of solvent viscosity and specific interactions on the rates of photoisomerization. Our results point to the fact that the positively charged as well as the negatively charged cyanine derivatives do not experience specific interactions with the ionic liquid such that the isomerization rates are affected. However, when the isomerization rates are compared with a conventional isoviscous solvent, it has been noticed that the rates of isomerization are solely governed by viscosity of the medium in case of the positively charged cyanine derivative. In contrast, photoisomerization rates of the negatively charged cyanine derivative are significantly faster in a conventional isoviscous solvent compared to the ionic liquid due to the specific interactions between the solute and the former, which lower the barrier height for isomerization.

show abstract

Dynamical solvation effects on the cis-trans isomerization reaction: photoisomerization of merocyanine 540 in polar solvents

Cited by 65 publications

References 1 publication

Thermal Back-Isomerization of Spirocyclic Naphtho-oxazine and Phenanthro-oxazine Derivatives in Alcohols, Nitriles, and Poly(alkyl methacrylates)

Thermal Back-Isomerization of Spirocyclic Naphtho-oxazine and Phenanthro-oxazine Derivatives in Alcohols, Nitriles, and Poly(alkyl methacrylates)

Universality in Isomerization Reactions in Polar Solvents

The role of specific interactions on dynamical processes in a room temperature ionic liquid

Contact Info

Product

Resources

About