Please include up to 4 more topics above besides "XRD Analysis" to get the most participation by the experts in RG. I'd also suggest inviting & soliciting the opinion of other experts that you may have come across in your RG surfing.

Please indicate the material system that you are particularly interested in as well. There are a few other related discussions that I'll post references to help. What is the substrate used for the polymer thin films? Can you use a known standard for this purpose with well defined XRD peaks? Do you have a typical diffractogram from your polymer thin film material? What are the dimensions of your "thin films"? How thick is thin? Do post some literature references for your material of interest.

As a general response, the key difference between "GIXRD" & the "normal mode of measurement" is the examination depth (penetration depth, or real space VOXEL size). The grazing incidence condition minimizes the penetration depth of the X-ray beam and the observed XRD is limited in sampling depth i.e., XRD information is that from the "topmost layer". You also have the option of using a longer wavelength

incident beam to reduce penetration depth further.

I'd also encourage a thorough review of the following classic:

Our materials are thiophene based polymers, PEDOT, P3HT,PDHPD etc.Thin films are prepared by different techniques on glass slides as well as Si/Sio2 substrates.Not yet found a polymer standard, Instrument is checked with Standard silicon which came with the machine.We make films by spin coating or dropcasting, so the thickness can vary from 50nm to microns(mostly in 100-300nm range).The following image is typical xrd profile done in normal mode

The material is P3HT

https://www.researchgate.net/publication/234896282_Solubility-driven_thin_film_structures_of_regioregular_poly%283-hexyl_thiophene%29_using_volatile_solvents

Article Solubility-driven thin film structures of regioregular poly(...

Great job with the back-ground info, Sreelekha!

Have you indexed the pattern and identified the peaks?

Do you have the XRD data from the substrate without the film?

Can you send me all the XRD data as Excel files with just the relative intensity in one column or row? Please include start angle, stop angle and increment. What was the dwell time?

At what angle do you expect the film crystallization to appear? Where is the "glass" or amorphous "hump"? What is your incident beam wave length? K Beta filtered? Why did you stop at 30 deg. 2-Theta? What is the 5 deg. 2-theta Bragg peak due to? What is the "hump" around 25 deg. 2-theta?

I just shared your question with my "followers" on RG and in our LinkedIn group, "X-ray Diffraction Imaging for Materials Microstructural QC". Please feel free to join, share and participate:

http://www.linkedin.com/groups?mostRecent=&gid=2683600&trk=my_groups-tile-flipgrp

[email protected]

It would be advisable to prepare some standard with different known degrees of crystallinity and recorded their XRD pattern. DSC is traditionally used to measure polymer crystallinity.

Hi,

we performed some XRD measures on PLLA and PLCL and estimated the size of crystalline domains with the Scherrer equation. Please see attached contribution. I hope it helps.

Sorry Susana! Here are some serious challenges in the interprettation of the XRD data in this publication above:

1. Incorrect use of the Scherrer Equation:

 "Where τ is the coherent diffraction domain, K is the shape factor, λ is the X-ray wavelength (copper Kα), βτ (=B-b) is the line broadening at half the maximum intensity (FWHM) in radians, being B the observed width and b the instrumental width and θ is the Bragg angle."

β is integral bredth not FWHM.

2. No mention of "preferred orientaion and its effects?

3. Beam conditioning?

By using scherrer formulla