ON THE EXAFS DETERMINATION OF THE SITE FOR THE CHEMISORPTION OF SELENOPHENE ON SULFIDED NI-MO AL2O3/

Simulation of the Mo and Ni K-edge EXAFS spectra of sulfided Ni-Mo/Al2 O3 catalysts shows that the Mo EXAFS spectrum is rather insensitive to the chemisorption of selenophene; this means that, in contradiction t o a former claim the site for selenophene chemisorption cannot be dete rmined from a comparison of the influences of selenophene chemisorptio n on the Mo and Ni EXAFS spectra. Experimental EXAFS spectra of a care fully sulfided Ni-Mo/Al2O3 catalyst showed no difference between Mo an d Ni K-edge spectra taken before and after adsorption of selenophene.