title: Pressure-induced polymerization of P(CN)3.
abstract: Motivated to explore the formation of novel extended carbon-nitrogen solids via well-defined molecular precursor pathways, we studied the chemical reactivity of highly pure phosphorous tricyanide, P(CN)3, under conditions of high pressure at room temperature. Raman and infrared (IR) spectroscopic measurements reveal a series of phase transformations below 10 GPa, and several low-frequency vibrational modes are reported for the first time. Synchrotron powder X-ray diffraction measurements taken during compression show that molecular P(CN)3 is highly compressible, with a bulk modulus of 10.0 ± 0.3 GPa, and polymerizes into an amorphous solid above ∼10.0 GPa. Raman and IR spectra, together with first-principles molecular-dynamics simulations, show that the amorphization transition is associated with polymerization of the cyanide groups into CN bonds with predominantly sp(2) character, similar to known carbon nitrides, resulting in a novel phosphorous carbon nitride (PCN) polymeric phase, which is recoverable to ambient pressure.
authors.affiliation: Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington, DC 20015, USA.
authors.forename: Huiyang
authors.initials: H
authors.lastname: Gou
authors.affiliation: NRC Postdoctoral Associate, Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC 20375, USA.
authors.forename: Brendan L
authors.initials: BL
authors.lastname: Yonke
authors.affiliation: Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC 20375, USA.
authors.forename: Albert
authors.initials: A
authors.lastname: Epshteyn
authors.affiliation: Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington, DC 20015, USA.
authors.forename: Duck Young
authors.initials: DY
authors.lastname: Kim
authors.affiliation: High Pressure Collaborative Access Team, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439, USA.
authors.forename: Jesse S
authors.initials: JS
authors.lastname: Smith
authors.affiliation: Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington, DC 20015, USA.
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Strobel