Table 4. P 2p Peaks BE and FWHM Values Obtained for the Different Glasses from XPS Spectra (Figure 5).

glass	P 2p XPS
	BE (eV)	fwhm (eV)
Ba	133.6	2.4
Nd	133.3	2.3
Gd	133.6	2.3
Yb	133.8	2.2