Tetrahedrally bonded dense C2N3H with a defective wurtzite structure: X-ray diffraction and Raman scattering results at high pressure and ambient conditions

DOI: 10.1103/PhysRevB.80.104106

Authors: Ashkan Salamat (University College London) , Katherine Woodhead (University College London) , Paul Mcmillan (University College London) , Raul Quesada (University College London) , Aisha Rahman (University College London) , Davy Adriaens (University College London) , Furio Corà (University College London) , Jean-philippe Perrillat (European Synchrotron Radiation Facility)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review B

State: Published (Approved)
Published: September 2009

Abstract: Synchrotron x-ray diffraction and Raman scattering data supported by ab initio calculations are reported for the dense tetrahedrally bonded phase (C2N3H) with a defective wurtzite (dwur) structure synthesized by laser heating from dicyandiamide (C2N4H4) at high pressure in a diamond anvil cell. This work confirms the structure deduced in previous work from electron diffraction experiments. The phase (Cmc21) is recoverable to ambient conditions. The ambient pressure volume (V0=137.9 Å3) and bulk modulus (K0=258±21 GPa) are in excellent agreement with density functional calculations (V0=134.7 Å3; K0=270 GPa). The calculated Raman frequencies and pressure shifts are also in good agreement with experiment. Ammonia (P212121) was identified among the reaction products as expected from the synthesis reaction.

Subject Areas: Physics


Instruments: I15-Extreme Conditions