ESCA studies of some niobium compounds

Binding energies of $\text{3d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}$ level of niobium in some of its compounds have been investigated using X-ray photoelectron spectroscopy. The shift ΔBE in binding energy of $\text{3d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}$ level of niobium in its several compounds with respect to that in niobium metal can be expressed by the relation ΔBE = i[B_5s + (m ? 1)B_4d], where i and m are the overall ionicity and valence of niobium in a compound.