Related Experiment Video
Updated: Nov 4, 2025

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Relations between absorption, emission, and excited state chemical potentials from nanocrystal 2D spectra
Jisu Ryu1,2, Samuel D Park1,3, Dmitry Baranov1,4
1Department of Chemistry, University of Colorado, Boulder, CO 80309-0215, USA.
Abstract:
For quantum-confined nanomaterials, size dispersion causes a static broadening of spectra that has been difficult to measure and invalidates all-optical methods for determining the maximum photovoltage that an excited state can generate. Using femtosecond two-dimensional (2D) spectroscopy to separate size dispersion broadening of absorption and emission spectra allows a test of single-molecule generalized Einstein relations between such spectra for colloidal PbS quantum dots. We show that 2D spectra and these relations determine the thermodynamic standard chemical potential difference between the lowest excited and ground electronic states, which gives the maximum photovoltage. Further, we find that the static line broadening from many slightly different quantum dot structures allows single-molecule generalized Einstein relations to determine the average single-molecule linewidth from Stokes' frequency shift between ensemble absorption and emission spectra.
More Related Videos
07:11ARL Spectral Fitting as an Application to Augment Spectral Data via Franck-Condon Lineshape Analysis and Color Analysis
Published on: August 19, 2021
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
Related Concept Videos
Molecular Spectroscopy: Absorption and Emission
Atomic Spectroscopy: Absorption, Emission, and Fluorescence
UV–Vis Spectroscopy: Molecular Electronic Transitions
Emission Spectra
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
Atomic Emission Spectroscopy: Lab