Journal of Synchrotron Radiation

Volume 15, Part 5 (September 2008)

short communications

J. Synchrotron Rad. (2008). 15, 532-534 [ doi:10.1107/S0909049508014283 ]

Calibration method at the N K-edge using interstitial nitrogen gas in solid-state nitrogen-containing inorganic compounds

A. W. Gillespie, F. L. Walley, R. E. Farrell, T. Z. Regier and R. I. R. Blyth

Abstract: The standard method of soft X-ray beamline calibration at the N K-edge uses the [nu] = 0 peak transition of gas-phase N₂. Interstitial N₂ gas trapped or formed within widely available solid-state ammonium- and amine-containing salts can be used for this purpose, bypassing gas-phase measurements. Evidence from non-nitrogen-containing compounds (KH₂PO₄) and from He-purged ammonium salts suggest that production of N₂ gas is through beam-induced decomposition. Compounds with nitrate or nitrite as anions produce coincident features and are not suitable for this calibration method.

Keywords: XANES; NEXAFS; calibration; nitrogen; K-edge; ammonium; sulfate; phosphate; chloride; nitrate; nitrite; hydroxylamine.