Does these attributes are defined by buildingSMART or not?

Hi @tandeep, sorry for the late reply. I see you are using FreeCAD. I can help you with this, but I will need more information, but this forum is not the right place for detailed individual vendor support.

Can you please post here: https://forum.freecadweb.org/viewforum.php?f=39

Please include:

  1. A copy of your FreeCAD file that we can use to replicate the issue
  2. Which version of FreeCAD you are using
  3. Attach the IFC you have exported from it
  4. Explain the issue again on that forum post for completeness.

Please also send me an email (I have messaged you my email address) with the thread link, and I will help you debug your issue and make sure that FreeCAD authors the IFC file as expected.