You are asking for a PCR file of TTB (presumably tetragonal tungsten bronze structure type) because you can't refine from a CIF file.

Quick clarification:

PCR files are input files that are employed inside FullProf (popular Rietveld refinement program).

CIF files (Crystallographic Information Files) usually come from databases like ICSD, COD, or experiment data, but they typically need to be converted or edited before you can employ them in FullProf.

Straight answer:

Unfortunately, no one generally places ready-to-use PCR files for structures such as TTB in the public domain. Instead, you normally:

Convert the CIF file into a plain PCR file with the help of programs like PowDLL, FullProf WinPLOTR, or GSAS-II.

Then you adjust parameters manually in the PCR file (background, profile parameters, etc.).

Things you can do:

I can help you build a basic PCR file from your CIF.

If you give me the CIF file (or even just cut and paste its content here), I can help you convert it to a basic PCR template that you can start refining.

Alternatively, if you'd rather, I can guide you through manually generating a PCR from the CIF using software such as WinPLOTR.