The P(1s) and P(2p) XAFS spectra of elemental phosphorus, theory and experiment

Abstract

X-ray absorption spectroscopy was used to study the local structure and chemical bonding of elemental phosphorus. Three allotropes of this element exist in the solid state. The most common of these is the amorphous red phosphorus. The other two are crystalline: white phosphorus and black phosphorus. In the gas phase tetrahedral P4 molecules are stable up to ∼ 800 °C. At higher temperatures P2 molecules become dominant.Theoretical P(1s) and P(2p) XAFS spectra of gaseous and solid state phosphorus were calculated by ab initio FEFF and GSCF3 methods. These were compared and the spectral features were related to structural and electronic properties of the different allotropes of elemental phosphorus. The calculation results were then used to explain the features observed in the experimental P(1s) and P(2p) spectra of red phosphorus that were measured using synchrotron radiation.