Optical band gap of a cobalt ferrite

[sounouhid]

Hi everyone
How can I determine the optical band gap of a cobalt ferrite film deposited on a glass substrate using its absorption, transmittance and diffuse reflectance spectrum (knowing that I don't know the thickness of this film)

 

[Vagn]

You would usually use a Tauc plot.

 

[sounouhid]

thanks Vagn for replying me
but i don't have the thickness of the film (so i can not determine the absorption coefficient alpha that i need for the tauc plot)

 

[Vagn]

thanks Vagn for replying me
but i don't have the thickness of the film (so i can not determine the absorption coefficient alpha that i need for the tauc plot)

You can plot αd instead of α.

 

[sounouhid]

and how can i determine the band gap from that plot

 

[Vagn]

and how can i determine the band gap from that plot

Replace the α's for the Tauc plot with αd's. As d is constant, it just changes the scale.

 

[sounouhid]

i will do it
thank you i really appreciate your help