title: Phosphine and phosphine oxide groups in metal-organic frameworks detected by P K-edge XAS.
abstract: Phosphine metal-organic frameworks (P-MOFs) are crystalline porous coordination polymers that contain phosphorus functional groups within their pores. We present the use of X-ray absorption spectroscopy (XAS) at the P K-edge to determine the phosphine to phosphine oxide ratio in two P-MOFs with MIL-101 topology. The phosphorus oxidation state is of particular interest as it strongly influences the coordination affinity of these materials for transition metals. This method can determine the oxidation state of phosphorus even when the material contains paramagnetic nuclei, differently from NMR spectroscopy. We observed that phosphine in LSK-15 accounts for 72 ± 4% of the total phosphorus groups and that LSK-12 contains only phosphine oxide.
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland. j.a.vanbokhoven@chem.ethz.ch.
authors.forename: F L
authors.initials: FL
authors.lastname: Morel
authors.forename: S
authors.initials: S
authors.lastname: Pin
authors.forename: T
authors.initials: T
authors.lastname: Huthwelker
authors.forename: M
authors.initials: M
authors.lastname: Ranocchiari
authors.forename: J A
authors.initials: JA
authors.lastname: van Bokhoven
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D009942:Organometallic Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D010720:Phosphines / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D016062:Porosity; D056928:X-Ray Absorption Spectroscopy; D014961:X-Ray Diffraction
chemical_list: D009942:Organometallic Compounds; D010087:Oxides; D010720:Phosphines; D011108:Polymers; D010758:Phosphorus; C044646:phosphine