Discussion Overview
The discussion centers around determining the optical band gap of a cobalt ferrite film deposited on a glass substrate, utilizing its absorption, transmittance, and diffuse reflectance spectrum. The challenge presented is the lack of knowledge regarding the film's thickness, which complicates the calculation of the absorption coefficient needed for analysis.
Discussion Character
- Technical explanation, Conceptual clarification, Homework-related
Main Points Raised
- One participant inquires about methods to determine the optical band gap without knowing the film thickness.
- Another participant suggests using a Tauc plot as a common approach for this determination.
- A participant expresses concern about the inability to calculate the absorption coefficient due to the unknown thickness.
- It is proposed that instead of using the absorption coefficient α, one could plot αd (where d is the film thickness) to circumvent the issue of not knowing d.
- Further clarification is provided that replacing α with αd in the Tauc plot will only change the scale, as d is constant.
- A participant expresses gratitude for the assistance received in the discussion.
Areas of Agreement / Disagreement
Participants generally agree on the use of a Tauc plot but have not reached a consensus on the implications of using αd instead of α, particularly regarding the determination of the band gap.
Contextual Notes
The discussion highlights the limitation of not knowing the film thickness, which affects the calculation of the absorption coefficient and the subsequent analysis of the optical band gap.
Who May Find This Useful
Researchers and students interested in optical properties of materials, particularly those working with thin films and absorption spectroscopy.