Related Experiment Video
Updated: Apr 25, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Orientational and vibrational relaxation dynamics of perylene in the cyclohexane-ethanol binary solvent system
1Department of Chemistry, Michigan State University , 578 South Shaw Lane, East Lansing, Michigan 48824, United States.
Abstract:
The rotational dynamics and vibrational population relaxation of the nonpolar probe molecule perylene have been studied in a series of ethanol-cyclohexane binary solvent mixtures, with the goal of relating solvent system composition to local organization. Steady-state spectroscopic data show that there is a discontinuous dependence of the spectroscopic origin on binary solvent system composition for perylene. Both rotational diffusion and vibrational population relaxation time constants show a clear discontinuity between 5% and 7.5% (v/v) ethanol in cyclohexane, suggesting a discontinuous change on molecular scale rearrangement in the chromophore local environment. We interpret these results in the context of the chromophore residing in an environment that is not homogeneous on the molecular scale and changes in its average conformation with binary solvent system composition.
More Related Videos
08:54Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
Published on: January 25, 2020
10:35Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Related Concept Videos
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
Chair Conformation of Cyclohexane
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
Conformations of Cyclohexane
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.