1. nanoHUB U: Organic Electronic Devices
Lecture 1.1:
An Introduction to Organic Electronic Materials
Errata – Changes to Slides 10 and 11
Bryan W. Boudouris
School of Chemical Engineering
Purdue University

2. Determination of the Weight-average Molecular Weight (Mw)
Polymers Contain a Mixture of Macromolecular Sizes
6-mer
10-mer
16-mer
M0 = 100 g mol-1
Molar Mass of a Repeat Unit:
Molecular Weight of an i-mer with i number of repeat units:
Weight Fraction of an i-mer:
Weight-average Molecular Weight:

3. Dispersity (Ð) and the Impact on Organic Electronic Devices
Dispersity is a Measure of the Molecular Weight Distribution
Dispersity of a Polymer:
Dispersity of < 1.3 Can Be Thought of As Narrow
Because:
, Then:
Dispersity Can Be Thought of in Terms of the Standard Deviation from the Average:
Narrowing the Dispersity (i.e., Minimizing the Standard Deviation in) of the Polymer Chains, Increases the Ability of the Polymer to Achieve a Higher Degree of Crystallinity. This, in turn, Increases the Charge Transport Ability of the Polymer in the Solid State.

4. nanoHUB U: Organic Electronic Devices
Lecture 1.5:
Structural and Optical Characterization
Errata – Change to Slide 11
Bryan W. Boudouris
School of Chemical Engineering
Purdue University

5. Large Difference in Absorption Between Solution and the Solid States
P3AT: Solution State
UV-Vis Absorption Spectra
P3AT: Solid State
UV-Vis Absorption Spectra
Polymers in ~1 μM chloroform solutions
Spun-coat from chloroform for a
Final film thickness of ~80 nm
Further Reading: Ho, V.; Boudouris, B. W.; Segalman, R. A. Macromolecules 2010, 43, 7895.
Polymers in ~1 μM chloroform solutions
The Shift to Longer Wavelengths (Red Shift) is Due to Solid State Aggregation

6. nanoHUB U: Organic Electronic Devices
Lecture 2.2:
The Schrödinger Equation
Errata – Change to Slide 4
Bryan W. Boudouris
School of Chemical Engineering
Purdue University

7. Derivation of the 1-Dimensional Schrödinger Equation (Part II)
Substitution of the 2nd Equation into the 1st Equation of the Last Slide Yields:
Taking the Partial Derivative with Respect to Time Yields:
Now, The Expression is Solely a Function of Position

8. nanoHUB U: Organic Electronic Devices
Lecture 2.5:
Carrier Densities in Intrinsic Semiconductors
Errata – Change to Slide 9
Bryan W. Boudouris
School of Chemical Engineering
Purdue University

9. Calculation of the Hole Density (Part II)
Integrating Over the Definite Integral Yields The Following
Often, The Effective Density of States for the Valence Band (Nv) is Defined:
So, The Following Holds

10. nanoHUB U: Organic Electronic Devices
Lecture 3.1:
Charge Transport via a Hopping Mechanism
Errata – Change to Slide 5
Bryan W. Boudouris
School of Chemical Engineering
Purdue University

11. Rate of Electron Transfer is More Useful Than Probability
If we assume that there will be a distribution of final energy states and that these probability densities can be integrated over all the possible values (i.e., over long times) and that the vibrational mode energies are significantly less than the thermal energy available, we can extract the following for the rate of electron transfer from the initial to the final states (kif).
Change in Gibbs Free Energy
Reorganization Energy
We Can Rewrite the Electronic Coupling Matrix as Simply Vif and
Further Reading: Marcus, R. A.; Sutin, N. Biochimica et Biophysica Acta 1985, 811, 265.

12. nanoHUB U: Organic Electronic Devices
Lecture 3.4:
Transport in Disordered Semiconductors
Errata – Change to Slide 11
Bryan W. Boudouris
School of Chemical Engineering
Purdue University

13. GDM with Spatial Disorder (Part II)
Then, the Mobility Can Be Written As:
Width of Gaussian Distribution
Site Spacing Constant
At high electric fields, the first path dominates but at very large Σ or low fields, the meandering path will dominate.
First Path – Moves with the Electric Field, But Large Gaps (large Σ) To Get There
Electric Field
Second Path – Smaller Steps, but It Is Against the Electric Field At Some Points