Synthesis and characterization of a binary noble metal nitride

Abstract

There has been considerable interest in the synthesis of new nitrides because of their technological and fundamental importance. Although numerous metals react with nitrogen there are no known binary nitrides of the noble metals. We report the discovery and characterization of platinum nitride (PtN), the first binary nitride of the noble metals group. This compound can be formed above 45-50 GPa and temperatures exceeding 2,000 K, and is stable after quenching to room pressure and temperature. It is characterized by a very high Raman-scattering cross-section with easily observed second- and third-order Raman bands. Synchrotron X-ray diffraction shows that the new phase is cubic with a remarkably high bulk modulus of 372(+/-5) GPa.

High-pressure studies with x-rays using diamond anvil cells

“…1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 pressure induces bonding changes [587,588], amorphization [589], changes in quencheability [74,590], metallization [591], and novel structures [393,[592][593][594][595][596][597][598][599]. Many exotic nitrides have been synthesized under HP [22, [600][601][602][603][604], including new durable noble Ir, Pt, and Os metal nitrides synthesized at HP coupled with laser heating [605][606][607]. These new compounds have bulk moduli comparable to those of traditional superhard materials.…”

Synthesis of Alkaline Earth Diazenides MAEN2(MAE= Ca, Sr, Ba) by Controlled Thermal Decomposition of Azides under High Pressure

“…15−23 According to structural and electronic considerations, these noble metal compounds are assumed to contain 4-fold negatively charged nitrogen dimers having the composition M 4+ [N 2 ] 4− . 15−24 Unlike the alkaline earth diazenides, the latter anions (bond length about 1.41 Å) 15 15−24 and their remarkable properties (e.g., superconductivity, photoluminescence, magnetism and low compressibility comparable to that of c-BN) 15−24 justify the investigation of the crystalline structure, stability, elasticity and electronic structures of the diazenides. However, except for M = Sr, Ba, Os, Ir, Pd and Pt, no other metal diazenides or pernitrides of formula type MN 2 have been synthesized in crystalline form as yet, but have been predicted by density-functional calculations to form under HP/HT conditions.…”

First-principles calculations of a high-pressure synthesized compound PtC

“…But it is impossible to distinguish between the zinc-blende (space-group number 216) and rock-salt (space-group number 225) structures solely from the x-ray diffraction because of the large mass difference between Pt and C. In this case, the Raman spectrum is an important criterion. For example, B.Gregoryanz et al [2] synthesized PtN at high temperature and high pressure and the crystal structure of PtN has a cubic symmetry from the X-ray diffraction. They concluded that the PtN has a zinc-blende structure because the rock-salt structure doesn't have a first-order Raman spectrum.…”