I have been doping rutile TiO2 with various transition metals. I have a powder XRD pattern of possibly Ti0.3W0.299Co0.001. The peak shifts, as compared to a literature spectra of TiO2 indicate that W is present in the unit cell. However, is there any way I can tell of Co has been incorporated into the rutile cell? I know that Co will not show up in the XRD pattern because it is less than 2% of the sample. Is there any way I can find out if Co has been incorporated into the unit cell without using a SEM? ]