title: Phosphine polymerization by nitric oxide: experimental characterization and theoretical predictions of mechanism.
abstract: A yellow solid material [P(x)H(y)] has been obtained in the reaction of phosphine (PH(3)) and nitric oxide (NO) at room temperature and characterized by thermogravimetric analysis mass spectrometry (TGA-MS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. In this work using complete basis set (CBS-QB3) methods a plausible mechanism has been investigated for phosphine polymerization in the presence of nitric oxide (NO). Theoretical explorations with the ab initio method suggest (a) instead of the monomer the nitric oxide dimer acts as an initial oxidant, (b) the resulting phosphine oxides (H(3)P=O <--> H(3)P(+)O(-)) in the gas phase draw each other via strong dipolar interactions between the P-O groups, and (c) consequently an autocatalyzed polymerization occurs among the phosphine oxides, forming P-P chemical bonds and losing water. The possible structures of polyhydride phosphorus polymer were discussed. In the calculations a series of cluster models was computed to simulate polymerization.
authors.affiliation: NIST Center for Theoretical and Computational Nanosciences, Physical and Chemical Properties Division, Gaithersburg, Maryland 20899, USA. yi-lei.zhao@nist.gov
authors.forename: Yi-Lei
authors.initials: YL
authors.lastname: Zhao
authors.forename: Jason W
authors.initials: JW
authors.lastname: Flora
authors.forename: William David
authors.initials: WD
authors.lastname: Thweatt
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Garrison
authors.forename: Carlos
authors.initials: C
authors.lastname: Gonzalez
authors.forename: K N
authors.initials: KN
authors.lastname: Houk
authors.forename: Manuel
authors.initials: M
authors.lastname: Marquez
mesh_terms: D003198:Computer Simulation; D007536:Isomerism; D008958:Models, Molecular; D015394:Molecular Structure; D009569:Nitric Oxide / Q000737:chemistry*; D009609:Nitrous Oxide / Q000737:chemistry; D010084:Oxidation-Reduction; D010720:Phosphines / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D010720:Phosphines; D011108:Polymers; D009569:Nitric Oxide; C044646:phosphine; D009609:Nitrous Oxide