Hope somebody can help me. I`m currently doing analysis of determining single crystal of Zr2Cu on a surface of bulk metal. Through XRD, i determine the peak and compared it with data from JCPDS card. My problem is I don`t know the correct way to compare the theoritical 2theta peak(from JCPDS) with the experiment 2theta peak. I mean how to prove that, like for example the 50degrees peak from experiment is comparable with 53degrees peak of theorotical 2theta, based on relative ratio calculation or sth like that? Sorry if I sound confusing pls tell me.