Sodium Dihydrogenpyrophosphate Hexahydrate (Na2H2P2O7⋅6H2O) by XPS

We report the XPS spectra of sodium dihydrogenpyrophosphate. XPS spectra were collected with a VSW HA150 x-ray photoelectron spectrometer using monochromatic Al Kα x-radiation. Monochromatic radiation provides a distinct clarity to the rich peak structure in the valence band of sodium dihydrogenpyrophosphate due to the absence of interfering x-ray satellites from the intense O 2s region. The features seen in the valence band are unique to the (H2P2O7)2− ion which shows small but significant differences from the (P2O7)4− ion. The valence band, survey, Na 1s, O 1s, C 1s, P 2s, P 2p, and Na 2s levels are reported.