I am working on DFT code having plane wave along xy axis and bspline in z direction. For calculating the properties of TMD materials, spin orbit coupling must be included but i did not find fully relativistic uspp pseudo-potentials of atoms that can be generated from vanderbilt code. Then I get it from Quantum Esspresso UPF format. but not able to parse it. I did not find it in web. can somebody help to convert it uspp format or any txt format so that i can extract parameters from it. Thank you!
USPP is not a format of pseudopotential. It is a type of pseudopotential that enables you to work with lower cutoffs. On the other hand, upf is a popular file extension for pseudopotentials.
If your question is regarding the availability of fully relativistic Ultrasoft PPs, they aren't very popular but PSLibrary offers that support.
For Norm-conserving and Projector-augmented wave PPs, Pseudodojo is pretty reliable (for both relativistic and non-relativistic cases)
I really don't know any engine to convert between pseudopotential formats, but below you can find links to engines where you can generate pseudopotentials according to your own needs: